water leak is possibly a bust heater matrix & if anything like an evo....an absolute pain to remedy
- as quick-fix, try using e.g. radweld(more than one) ..to see if it stops
engine from a 1991-1994 Galant 2.0 gti twin-cam(non-turbo) is easiest option and will fit straight in & use same wiring
- rated at approx 150 bhp ...so will give good increase from your standard 1600/1800 unit
- a bigger project is using a vr4 turbo lump but major job with wiring/electronics
rather than using rad weld, easier and better to pull the hoses feeding the matrix from the bulkhead fittings and place a piece of pipe, jubilee clipped between them, bypassing the matrix. if its the matrix no more water, if still water then door seals or leak in bulkhead (missing gromets etc.). most likely to be matrix and i agree if similar to evo its a mare of a job.
you don't have to take out the dashboard but you do have to spend about 4 hours on your back in the wet footwell, upside down, cursing while trying to lever the pigging bits out. amazingly it all goes back together a lot easier than it is to take apart. i know i'll probabily be doing it again next weekend. the joy.