I have a 1954 Ford F-100 That someone has put a Mustang II Front end on, but they didn't put the power steering on it. It has the rack and pinion steering already put on. I was just needing to know what do i have to do to add power steering to what i have already, Thanks for any help you give

You will need
1) power rack and pinion
2) Power steering pump
3) steering pump bracket
4) pulley.. maybe 2 pullies, one for the pump and one a double groove for the crank pulley
5) belt
6) pump to rack hoses
7) depends on the pump you use, if you use a GM pump you'll have to put in a power steering value, to get the pressure down

Also, depending on the manufacturer of your cross member, you may have to notch the cross member to receive the fatter input shaft.

Trees

Unless you have some ridiculously wide tires on the front or an alignment problem you shouldn't need power steering.

You will want to use a bird rack not a pinto.(slower) Get the valve out of plymouth horizin pump. Its a gm pump but has a diff pressure setting for the rack on those little cars. The adjustable valves dont work. They dont turn the pressure down just slow the transition. I agree stick with the manual if it drives good. Have some pretty big cars with amnual racks. If you go power you will also want to put a bunch of caster in it also...forget the stock specs..car will be real touchy on the highway. They need upwards of 5-7 degrees to make em drive good. less with manaul cause it will be a bear to park with a lot of caster.