I just finished a CV swap on my 66 F100 a couple months ago. Some guys want their truck really low to the ground, I wasn't going for that look. In this pic you can see where I have a 2x4 between the frame and suspension. I landed up with a 2.5" x 5/8" plate there. It still gave me about 4" of drop from the "twin I beam". You will probably want more of a spacer then my 5/8" if you want to have the engine over the suspension. The truck had some lowering shackles in the back and I don't think I'll need to lower the rear anymore, if it does need it I'll just move the front shackle mounts up an inch or two.
When you get a CV from the wrecker have them cut the frame ahead and behind the suspension. There are 4 crush tubes that are threaded you'll want and the 8" long bolts to go with them. My local Ford dealer said the bolts are no longer available.
Mine was the "Twin I beam" and had a monster crossmember I had to cut out. After installing the crush tubes I boxed the frame and painted it with POR15.
The steering parts are from Summit, 3/4" 36 spline to 3/4DD. AND A 3/4DD to Ford triangle a 20" long piece of DD steering shaft.