Hi thanks for letting me join your forum, Iam looking forward to having some conversations and help with my project. I have several holdens from HD Ute, EH sedan, WB Ute Commodore VS Ute, and a HR Ute all of which are standard, original vehicles, however the Hr ute requires a lot of work, and I would like to modify it while Iam at it. So far I've spent a lot of time getting the body in shape however the floors are shot and has some very dodgee repairs over time and rough floor panels welded on top of rusted panels three deep a real mess so I wont to remove the lot and replace it with a complete full floor from a VS 1998 Statesman which remarkably have virtually the same dimensions give or take. The reason is, I have all the mechanicals looms for the V8 Auto so I really need the tunnel anyway and cross members. MY QUEASTION TO the tech people Can I DO THIS, HAS ANYONE DONE THIS

Agree with Dr Terry. Consult an Engineer in your State/Territory first.

HR's are relatively easy to do V8 conversions on as they are really just a HK underneath, but there are size rules, braking, seatbelts etc all that need to be sorted which is what you need an Engineer for. Changing a floor pan is a big thing.

The easiest HR V8 conversion is a SBC and V8 Powerglide, will bolt straight in using HK mounts and gearbox crossmember. A HR Powerglide column should operate it too but you have to deal with the steering which most do with a rack conversion. You can lighten up the SBC hugely to make is weigh less than a Holden V8 by using alloy heads, intake and water pump. If your Engineer limits you on engine size, a 283 in a HR would be really nice, if you run a 60 thou up bore (same deal with 307 as it is the same bore size) you can run 1985 era Corvette alloy heads that have 1.94/1.5 valves and 58cc chambers, these are cheap to buy and go really well even on a 327 or 350. You just need the slightly bigger bore for intake valve size. You can get tricky later on with a 283 too as almost all of them bore to 4", and any 1963 onwards will take a 327 crankshaft, so you can turn them into 307 (STD bore), 317 (60 thou) or 327 (125 thou). Or leave the stock 283 crank and make a 302.

The other combo that will work with the standard HR floor is a SBC and Trimatic, but you have to either find a Brazilian (GMH made) box with SBC bellhousing pattern or get an aftermarket bellhousing. These will go into a HR using HK-HG SBC mounts and adapters and a HD-HK Powerglide or M15 3spd gearbox crossmember, might have to extend the slots in the gearbox crossmember by about 20mm. I think a HK M15 speedo cable works. 253/304/308/350 should go in the same with a Trimatic and use HT-WB engine mounts and adapters (they all fit the same although the HT-HG ones look different). Anything else involves floor mods from memory.