65 dart 4speed drive shaft

Yes, plenty strong. Like Hemi strong.....Ball and trunion too. Your going to need to cut the driveshaft anyway to fit a better rear end if you still have the 7 1/4, that is the weak link. and if the driveshaft is tapered at the flanges so they cant cut 2 inches out of it (or whatever they deem necessary for your new 8.25/8.75 rear) youll need a long doner.