[McDeezl]

Forgot to mention what the solution ended up as for the throttle cable and linkage. Messed around with stock cables for too long and ended up getting a Lokar stainless braided cable and linkage assy - perfect!
So that's Lokar for the throttle, Lokar for the transmission shift linkage and won't even bother messing with stock stuff for the park brake cable assy .... just go with Lokar again. Checked on the stock park brake cables and there are about 20 different versions depending on year, 1/2 or 3/4, etc. Seeing as I have a '68 3/4 ton frame with a '72 1/2 ton cab on top, 350 sbc turnkey crate, etc I can't be bothered guessing at that .... Lokar.