Re: 1986 300 I-6 to V8 swap
I once put a 300I-6 into a 79 ford truck that had a 400M in it originally. Most of the mounting points were on the frame but all the brackets had to be changed. The motor mounts just unbolted and the I-6 mounts bolted in perfectly. Even the tranny crossmember bolted right up. The truck had a auto tranny which we scraped and replaced with a 4 speed manual. Aside from the different length there was no problem, the holes were in the frame and not used with the auto so it was only a matter of bolting the crossmember up in the right holes. In this case I used everything from the motor to the rear end so drive shafts and such matched right up. This was a 79 Twowheel drive but from what I have seen they did this wih many of the truks so if you are swapping in something that was optional you should be able to bolt it right up.
Good luck and if you can find all the parts you need at th salvage yard you will probably be golden.
[img]/wwwthreads_images/icons/wink.gif[/img]If it's stuck, force it! If it break's,it needed replacing anyway!!!