make sure it's an aw71, not an aw70-light duty. use your bellhousing on the 87 and off you go. first, i would pull the pan off the old 1. sounds like the shift shaft is outta place inside. there's a roll pin that connects the shaft to the selector gate inside the trans. drain it, pull the pan and you can tell by moving the outside linkage if the inside gate is moving. if it's moving everything into the right place, then swap the trans. if not, fixing yours is easier than the swap. good luck, chuck.