8 3/4 rear end worn out or not?

Thanks 5.7, so its the five bolts i have to undo right lol? So will i know how to spot if its worn out easily? Also where/what car can i remove the brake drums from so that i can change my bolt pattern?? My axles have 10 holes, right now theyre on 4 3/4 chevy bolt pattern ,( yes thats typed correctly), Im not crazy either. The axles have 4 1/2, and 4 3/4 bolt patterns, Like moser/yukon etc etc... But i need the drums for mopar pattern where can i score some? Thanks for any feedback