Talk to some of the other members, for instance Norkep ...
It will cost much more (and you may come across many pitfalls) to put a Supra engine in a GS, than replace all the Toyota emblems on an Aristo ...
You may end up spending GBP1x,xxx on conversion parts and service ...
Also ... your car may spend it entire life in the shop ...
If you go for an Aristo TT ... you can use it while modding ... and feeling the improvements of every single part ... that feels soooo good
And the engine of the Supra is the same as that of the Aristo, officially the Aristo TT is 280 hp (as is the JDM Supra), ... but in practice... 280hp is an understatement :P