You can either solder any WP connections with a copper pipe cap (it's probably brass), or yank them out, tap the WP (carefully) with a pipe tap - 1/2" is my recollection, and install a pipe plug. The one on the intake - a brass pipe plug should work. If you choose to yank it out of the WP, you only need a brass pipe nipple from Home Despot for a couple bucks to install a heater hose.

There's a bypass hose between the WP and manifold, just below the water neck - that can't be plugged. And unless you like cussing, install that little SOB of a hose when you install the manifold

On my 5.0, the hole in the water neck has my fan switch sender and the one in the manifold, my temp gauge sender.

(I just found my long lost '79 Ford P/U Engine shop manual and 460's are well featured there)