With the frame stiffening backing brackets, the frame rail does need to be notched, nor do I recommend doing so. There are many complete kits available. The key is finding the correct power steering pump mounting bracket, power steering pump pulley, water pump pulley, crank pulley, to work correctly and provide proper alignment. The short water pump and the long water pump require different mounting brackets & pulleys. Also, the hose fittings on the '80 & up power steering gear boxes & power steering pumps went to metric fittings, so make sure, whichever you use, both are SAE or metric, to ensure the fittings are compatible.
I have personally done the conversion on '63-'66 Chevy/GMC 2wd, 4x4, 1/2 ton & 3/4 ton trucks and although there are some subtle differences in the frame configurations, there conversion is very similar. I offer the frame plates, as well as, many of the other parts you need, so let me know if I can help.
Here is a good link for the conversion:
Power Steering Conversion
