Questions about disc brakes for front

[jgaley69]

I've been kind of looking out here trying tofigure it all out, currently have 1970 C/10 6 hole 2wd. Now reading that will need to atleast find some diffrent Spendles like from a 72? Have read into some telling what has to be replaced tie rods mostly? My question is arent the spindles the same Diameter and Lenght, have worked it up in mind that could be done without changing spindles or is this completely wrong?

I am one of these who will check everything out before parts are bought, never like listening to some of the parts guy with questions?