New owner what things should I change with the mach 1

I recently purchased a 70 MAch 1 ser # or05m149843. The car is far from perfect but has really no rust and is a driver at this time with about 130,000 miles. Everything is factory and numbers matching but like I said needs work.
I will be fixing it up a bunch but will not be a complete restoration. The engine is origanal but I am sure has been gone through before and it needs a rebiuld now.

What I would like to do is upgrade the brakes from drum frt to disc and change it over to rack and pinion steering. Biuld another cleavland engine that would make approx 450 hp and save the origanal one in a corner.

Nopt sure if the car should be kept as origanal?

Any thoughts would be helpful.

Since there are more 351 Mach's (like your's and mine) than Cobra engine models, I say modify it the way you want. Find some granada/monarch front spindles with disc brakes for a good Ford brake redo and built an engine that will run on unleaded and make way more power than our factory clevelands. Go for a TKO 5 speed if you can find one reasonably priced too.
Good luck and post some pics!