Civic EG

Okay quick explanation. Emergency situation called to drop in a spare motor I had laying around. Motor is a d15b2 from a '90 civic. Running p06 ecu, b7 wiring harness, b7 intake, b7 distributor, y8 trans. Newer gaskets all around.
I have compression in all cylinders, fuel and spark.
When I crank her over, she doesn't wanna fire. Started once or twice for a few seconds then died, hasn't done that for a week or so now though. Occasional backfire. Otherwise she just cranks and cranks.
Yes before asked if I've checked timing, I have. Over and over.
I feel as though ignition timing maybe off due to the b7 distributor. I have a spare b7 cam laying around. Would installing a b7 cam into b2 motor cause any issues? I know the b7 and b2 are basically the same except for obd difference.
If I were to install, b2 or b7 cam gear?

I'd post this on hondatech or d-series.org but I forgot my email for the account.
Any help and input is appreciated.

you know I had the same issue with my jdm d15b vtec, turns out the dizzy rotor seized up, then I put the new one on 180 off, get it to TDC then pull the cap off to verify its firing on the first plug wire, and also double check firing order if you haven't..hope that helps

The rotor seemed to be 180 off, but I've purchased another and they only seem to bolt back on 180 off. This is why I was wondering if the b7 cam could come into play.

im not sure about the b7 cam, I haven't done a lot of research on the internals of heads much, I just know that you should be able to take off the cap and re seat the dizzy, after I did that it fired right up but I had to adjust the timing on the dizzy by feel until I cant get a timing light, haven't run it since, but I need to also address a really high idle lol, think I got a vacuum leak after the throttle body somewhere lol. I hope you get it figured out because like I sad that same issue plagued me for about 2 weeks....