I don't mean to talk negative about a repair you want to do but I want to save you the hassle of repairing it again & again. I doubt JB Weld will work, if the housing broke, how will gluing it back together be stronger? If the JB is stronger than the housing (which I doubt) it will break directly beside the repair because that will be the weakest point. If JB is not stronger it will break in the same spot because if your starter broke, it did so for a reason.
If a stater is adjusted correctly, you have a good flexplate & your motor is running good, you won't have starter problems. My experience has been that the starter is either mis-adjusted, the ring gear is worn or there is another problem with the way the motor runs at startup.
Check the starter adjustment & the ring gear first. If those are perfect than check the timing then check the solenoid in the distributor. I've discovered a few over the years that cause a misfire at startup & caused starter troubles because they cause the motor to kick back periodically. It's not common but it's worth a try.
Best of luck
Happy New Year