Ya know, every car and engine swap is a little different. I put a '96 LT1 4L60E in my '85 745. Wiring wasn't hard, just took a lot of time reading and understanding BOTH the Volvo AND the engine/tranny wiring diagram. For sensors, the LT1 and 4L60E have sensors in the engine and tranny that communicate with the PCM through the stock wiring. I left those alone. When I want to add a gauge sensor, I just added another sensor into the block and ran an extra wire on the engine and hooked it into the Volvo harness. Having said that, I STILL can't get my Tach to function correctly. It is because the car was originally a diesel and is throwing me fits.

For the swap I modified my engine to OBDI (instead of the OBDII that the '96 is) and put on '95 exhaust manifolds. (my '96 headers had dual cats mounted in weird, non-fitting Volvo, ways.) I had the manifolds angle ground to bring the exhaust outlet port about 1 inch closer to the block/tranny. This provided for close, but adequate clearance around the frame rails. I might have had to trim one of the lips on the frame rail near the firewall... can't remember.

I didn't use the JTR kit because it didn't exist at the time. However, I bought about 4 of their manuals and studied them, paying VERY close attention to all of the pictures to see how they did things. In general, I think they do a pretty nice job. Any money that you spend with JTR, is money worth spent in my opinion.

You can look at my conversion here:
http://simondodd.home.comcast.net/volv8/

take care,
simon