I don't think there is such a thing as a "straigh drop" in engine conversion. There are always things you have to make or modify.
X2 even when i swapped in a 22RE into my 84, i still had to cut a hole in the firewall for the extra wiring, switched out the gas tank/lines, wiring, and a bunch of other stuff. i at one point almost put a 2L that i found in an 83 2WD but it didn't have a tranny with it and it would've been a hassle because rats and other creatures had nested in it and chewed through everything as it sat in a field. i fixed what i could and got it to run though and it still ran like a champ after sitting for years.
