I'm swapping in a D16Z6 in my 90 Hatch. The motor came with the engine harness and ECU. Is it a possibility, instead of cutting and splicing and doing electrical wizardry, to use the harness that came with the motor and buy a jumper/adapter for the body harness? I've found the jumper/adapter to go from OBD0 to OBD1, but will that later gen engine harness work or do I have to do a Frankenstein harness?

 

Not sure if it exists. You could talk to Rywire or Monotech about possibly making the jumper...they would know if it is possible. They will also sell you a plug and play harness if you want.

 

need more info.

is your car dx? si ? was the car the swap came out of also a dx or so? all your specs must match. and you will still need to do the mods at the way if your car is a dx.

if your a stock si body, and the swap came out of an si (keep in mind 88 and 89-91 si are different, if is also different). then you will just need the jumpers

 

I've been looking into the same thing, the general answer is no, there isn't a specific adapter. however, the swap has been done countless times, so the info is out there. It's also been done wrong/incomplete many times (search swap, no start) so there's that.
If you have somebody build you a harness, make sure they're reputable. I haven't heard many bad things about Rywire, but haven't dealt with them personally.