Badger Ridge makes a great conversion kit don't use some of the cheaper ones as the sear gets ruin on some of them, I bought a complete bolt from gun parts so I could go back to a cap!
I got badger to fit my 77 50 a few years ago. Best money I ever spent. I use Blackhorn209 ccurate, with no fumbling and no missfires, and a ice fellow to work with.
Bfly