Front End swap?

[Solver]

I have a 72 frame that is rusted bad by the back shock supports. I have lots of pre 71 frames. How much work is it to swap the whole front end out of my 72 into a pre 71 frame. I think there are 6 bolts holding the whole thing on but didn't know what else is involved. How do you make sure its lined up right? Seems like there is a bunch of shims or something up there. Am I better off just finding a cheap 72 frame?Would I unbolt the steering pump and move that with the unit or try and break the pitman arm free?just wanted a little input from someone who has done this.I have done the rear ends before so that is not a problem
Thanks