I found a '90 5.0 from a mustang to replace the one in my '83 F150 that's about to throw a rod.

Will there be any hang ups if I bolt everything from my '83 motor onto the '90 motor?

I'm in a tight spot and I need to get this engine replaced quick.

 

I think the only thing I need to do is put a steel gear on my distributor

 

Yes that's right about the distributor gear... otherwise everything will bolt right on. You will probably need to rejet the carb though.. the HO breathes much better than the old lump it's replacing.