Impreza Coupe conversion to WRX Sti

[WRCSWAP]

Hello.

I've been looking into building a rally car for the weekends, for the last few years and have been looking into 1st gen Impreza Coupes. 

Since 99% of the parts will be changed i don't want to spend 45 to 60k on a base WRX STi coupe so i've been looking into the base model Imprezas with AWD.

A local one is avaiable for around 8K, no rust, clean title and AWD with power steering. It will be swapped to an EJ20 turbo and a 6MT.

However i'm wondering if the Shell itself is different from proper WRX STi's. Does the WRX subframe bolt directly, does the engine bay require fabrication to mount all the stuff or do WRX parts bolt on directly.