went to the parts yard

so i should have no problem with the driveshaft i have in my cuda as of now? On the disc brake car 75 valient it has power brakes i believe, (well if it does) can i use the prop. valve cause i have manual brakes and are probably going to keep them that way. isnt the prop valve different? so should i even grab it from the donnor car for my cuda? how about the master cylinder shoudl i just get a reman one from a parts store and not even get the used one(well maybe for a core?)

http://www.moparts.com/Tech/Archive/axle/17.html
according to moparts the brake TO(edit)brake demetions are different so is the pumpkin and how far it 'sticks out' so i will need a different driveshaft. Will i have any problems cause the axle is 2 inches wider on what i got? any driveshaft sugestions? the one in my cuda was what appears to be is custom made its got a local driveline shop on it, i assume they could shorten it to whatever length i need.