Thanks on the info on PATC, didn't know all those gear variations were available. To my way of thinking, the speedo "final drive ratio" should end up the same as it was originally. That is, and I'm going from the HK Manual here, for 3.08 gears and 7.35 x 14 tyres (haven't investigated, but assuming it's about the same circumference as a modern replacement tyre)the drive gear has 20 teeth and the driven gear has 19, therefore about 1.05:1. Just looking at the PATC combinations, I can't see a drive and driven gear combination that will result in that same final drive ratio. Will be interesting to see what happens when you do your road test. Also, have you confirmed that our speedos do 1000 turns per mile of travel?

If lack of room is an issue with the speedo cable area on the box, there is a 90 degree speedo drive available that can help with the route of your cable.

Here's a link to a company that sells ratio boxes. There's a pic as well.
http://generalauto.com.au/Ratio.htm

It's taken a while, but have now done a couple of road tests with the new trans in place. Overall very happy with the change especially the longer legs with 4th gear.
A couple of things to sort out.
1. There is now a strong vibration at about 70 to 80 kph, which goes away at about 100 kph and up. If I shift to neutral at 80kph and coast, the vibration is still there.
I had a new tail shaft built locally(Darwin)which took them about a month to do. They commented it took a lot of work and time to get it to balance, and it has a fairly large balance weight attached. I suspect it to be the problem, but I am also aware of the importance to ensure the gearbox output shaft and diff pinion angles are parallel. I modified the tunnel area to get the trans up as high as possible, but I don't know if it is correct, should be close.
I've heard of using a protractor, does any one have a procedure to check the alignment? Engine is a 350 SBC.
2. The trans shift points need some work, 1st to 2nd shifts late at light throttle, and it will drop back from 4th to 3rd without throttle change. A local auto trans bloke suggested It's probably close, but back of the TV cable adjustment a couple of mm and road test to check shift changes. He showed me the stock cable adjuster and I see how it is a very fine and sensitive adjustment. He also said the pressure operated switch for 4th gear can be used for the converter lock up, but the switch also operated in 2nd gear, any one else found this?
Cheers.

HT Prem,did you sort out the correct throttle linkage/plate ratio to attach your cable that i mentioned a while ago?
If not you will be chasing your tail to get the correct shift pattern and can cause trans failure because the line pressures can
be all over the place ie the TV cable can be at say 60% pull,the throttle at 80% at max torque but the line pressure may be only 80psi
and can fry the clutches....(thats just a scenario that can happen)
Converter lock up happens in 2-3-4 on the TH700R4....it was about 4 years ago but i/we bypassed the trans temp switch on the valve body
which only locks the converter in 4th and i used a toggle switch to activate it when i cruised.
The lining on lock up converter is small and doesn't like a high/instant load on it (thats why they recommend towing in 3rd gear)
When i did the by-pass the load on the 3rd-4th gear change was noticeable because the TCC locked up straight away especially at low speeds.
I added the toggle switch so I could choose when it locked,BUT you have to remember to switch it off again.
There are ways of adding relays etc to cure that,but in the end i EFI'd my red motor to eliminate all that.
B&M sell a vaccum switch kit and i'm sure there are others that do it.
Do a search on oldholden.com and type in,TCC,TH700,lock up etc and you will find the wiring diagram and ways of doing it.
Its still the best mod i did to my HJ coupe because it cruises SO much better as you will find out.
cheers...Mario

Well it's been a bit over 12 months since the last post and a fair amount of cursing, test driving, more cursing.
Turns out my B&M trans had the wrong valve body and separator plate straight out of the box! The Aust distributor came to the party with replacement parts and rebuild kit, it was installed and the car now has 4 forward gears instead of 3.(symptom was the trans shifted from 1st to 3rd when in D).
The box shifts well now on light to moderate to throttle, but give it some more and it shifts 1st to 2nd then straight to 3rd quickly.
Also, manual shift from 1st to 2nd, the trans stays in 1st, shift again and it goes to 3rd. Shift down to 2nd from 3rd an it neutralizes!
Has anyone had similar experience with a TH700,or can recommend a good auto trans specialist to talk to?
Having said all this, the car is great to drive with the overdrive gear and lockup, so I want to persist with it to resolve these issues.

I have heaps of pics of my ute with the T700 in it, but none that show exactly what you are looking for. If no one else comes up with pics, I'll take some and post them up here. Won't be for about a week 'though. Actually, I was surprised at how easy it was. No mods to the firewall or tunnel, just had to modify that brace a bit.

Thanks some pics would be awesome!!! NO hurry I can wait! It does seem the floor brace is the biggest problem, does anyone know if it is an engineering defect to cut it? how did the speedo cable fit? Its funny the car had an aussie 4 in it and the middle section was cut right out! I put a trimatic in it after fixing it....perhaps i should have just left it out lol

with re the diff, i dont know how interchangeable all the parts are does anyone know for sure the US 10bolt gears fit the hktg 10 bolts? Are they hard to change? I guess i'd be happy with 3.08 gears altho the 4spd box gives the best of both worlds!

It is the same diff as a 1967-1969 Camaro with GMH made axles and ends so the gears will be identical to US stuff, just have to find out which.

We didn't have to cut the brace, just heat it and tap it in a bit. Used a CRS rear crossmember and a HK Saginaw rear mount. Speedo wasn't a problem. Used a ratio box at the gearbox output. My cable was a bit short, so I used a Corvette cable extension which is about 24 inches long. Here's a link http://www.ecklerscorvet...ter-cable-1969-1977.html