Hey i was just wondering what i would need to do to swap a 5 speed celica box from a 202 to a 253 ?

Going back way to many years! I remember in the 1970's that Geoff Dello(w) - Sydney - had a kit for this purpose. This included bell housing adaptor, hydraulic clutch and cross-member adaptor. I actually saw a modified EH with this (253) configuration. Additionally, the input shaft and tailshaft needed shop modifications. The clutch was a heavy duty pressure plate with a six spring driven plate.

The down sides were that the extreme lift in power often burnt out 5th gear, either bent or twisted tailshafts (most were hoons with wide tyres)or wore out universal joints; Repco racers (unis) and a V8 tailshaft were the contemporary solution to this latter problem. The purported solution to the 5th gear problem was to use a diff ratio of 3.55 or higher. Additionally, heat of the transmission was a problem. A high quality extreme application lubricant was recommended.

This is well and truly from the 'mists of time' but I actually saw the application. It also appeared in motoring magazines from that period as I remember reading an article.

Good Luck!

Petered