That engine is a boat anchor if you are looking for performance. You would be better off building an engine from the ground up than trying to make that 140 hp wonder go. 5.0 parts are cheap compared to a couple of years ago. If you are not in a hurry you can also score some good deals on used stuff that has seen little use from someone that has not completed a project or that is ready to upgrade again.

I would keep all of you old stuff handy.
That is a first year car and some people are looking to the 79 cobra mustang as a quasi collectible.