-you need to use 33 mounts with the 33, sits lower and has 2 bolt pattern onto the xmember rather than 32 1 bolt
- you could 'massage' it, might cause problems with oil flow, better to space the sway bar from the body, about 10mm
- would also be good to enlarge/baffle sump while it's out
- might be wrong with the 25, but I think you 32 bottom (if using 32 radiator) and 33 top hose
- front pipe can use rb25 , fits into the s13
- can keep ecu, seen a lot of 25's eating it lately with wolfs but might be just me
that's all I can think of atm