Figure out what disk brakes and rim bolt pattern you have. If it have 4 piston Kelsey Hayes calipers it's most likely 5 on 4" oddball 60-72 A-body bolt pattern.
Do you do the work like front suspension stuff yourself or pay someone to do it?
Jack car up and do a front end condition analysis. Like check wheel bearing adjustment, idler, pitman, tie rods, lower control arm bushings, strut bushings. Typical first things to go are the idler arm, driver side lower control arm bushing on a power steering car that leaks(leaked) on the bushing.
Transmission is most likely a 904. Need to look at trans pan bolt pattern to ID.
For rear end howl you should check what rear end you have before putting any money into it. First check the fluid level and fill it if its low. If it's a 7 1/4 rear, might be cheaper just to replace it with a good used unit. That or consider a 8 1/4 rear end with large bolt rim pattern. That decision might factor in with what condition and type your front disk are.
