Trying to put a 1987 B2000 engine in a 1987 B2200 truck

I'm new to Mazdas and hopefully you guys can answer this question for me. I can get a really good deal on a B2000 with low miles for cheap The motors look almost identical and from what I can see most of the connectors line up. Now the tricky part: the internet indicates that there are 2 different part numbers for the B2000 and the B2200 ECU which I'm assuming means they won't interchange. I recoil in horror from the idea of gutting the cab to strip out all the wiring and hopefully I don't have to. Anybody with any experience to pass along would be much appreciated. Thanks in advance for your time.

will swap with no problem what so ever. engine will plug and play. no need to remove any of the wire harnesses. pull out old engine, insert new engine, put on your accessories, wire it up the same, drive away happy.

You knew that was exactly what I wanted to hear, didn't you?

OK, I'm going for it, but one more question: why do they have 2 different ECUs if they both do the same thing?

cali emissions versus federal emissions. stick with your ecu, it won't notice the difference.