The 8 3/4 are good solid rear ends and can handle allot of abuse (been there, done that).
The weak link that limiting them is the yoke connection to the drive shaft. Mopar’s use metal straps to bolt the universal cups to the yoke. The bolts used are way too small (5/16"–24) and tend to sheer off
when the tires or slicks hookup and grap with high torque/horsepower 450-500+HP engines.
To fix this most people change the yoke with a billet yoke using U bolts and if its a 489 type third member they also change the pinion crush sleeve with a solid sleeve. In addition use Lakewwod solid universal joints. After that they're good to go around 600-700+HP or until the axles snaps....
Dana 60 are good to go as-is up to the 600-maybe 700+HP using only a cover gridle for modification, but the cost of the rearend is expensive and an extra 35 pound of weight.
Enjoy!
