Stop!
Brain food, get a 240sx!!! BTW, I bought the same bodykit a year ago and I never had time to put it on my 90' 240sx!!!! The kit is sitting in my back yard collecting dust and you just gave me some momentum, good work
I just helped a friend did a SR20DET swap, the engine is smaller than the KA24DE(US) motor, it goes into the engine bay with the transmission very easily(unlike my VR4).
The FWD SR20DET from the SE-R WILL NOT WORK with the 240sx, you need to get the s13-s15 engine from Japan. The older red top SR20DET from the S13 pops 205 HP and it whould cost $1600-$2800, a $2800 engine should include the Engine, ECU, uncut engine wiring harness, tranny, chips, MAS. The S14 S15 engine are alot harder to find and more expansive. S15 has a 6 spd tranny and 225 HP.
The US spec SR20DE is different than the Jspec, but they have alot of parts that are interchangeable so finding parts are not hard.
The SR20DET is great, but a turbo KA24DET engine will cost you about the same money but more HP. Stock S13 SR20DET should do 14.5 in 1/4 mile, but a stock KA24DE with the T3/T4 turbo will get you into 13.9 easily.