If you read the thread "why don't parts fit? I now am the proud owner of a new oil pump/distributor driveshaft that has a bent hex end. I could get the gear off i suppose, and swap it onto the old one with the worn gear, but i have never done it nor do i have a replacement pin for reassembly . I need to know how to do this correctly, as a mistake can cause serious damage. Thanks.

I've never done it, but it's not supposed to be hard. There should be no need for a replacement pin. The Mopar drive uses a 1-1/4" long #3 tapered pin, the Milodon uses a 3/16" x 1" roll pin.

A tapered pin is, of course, bigger on one end than the other. Take your dial calipers and find out which is the big end. Use a punch and tap it out in the right direction. A normal punch is what nearly everyone would use to drive out a roll pin. Below
is a picture of a 3/16" roll pin punch. A roll pin punch has a little tit on the end to keep it in place for you when you are getting started. And it is a few thou undersize to help when you are going through to hole. (A normal punch is also slightly undersize, possibly for the same reason.) Don't give up, you can do it. People sell gears, so I know people change them.

I replaced the bronze gear I had with a melonized gear. The bronze gear was pinned but also shrink fitted to the shaft. I put some pressure on it then warmed it with a hand torch and it let go.

I have done it and yes, it’s tough. First, grind the ends off the existing pin flush with the gear. NOTE that the pin Is NOT tapered - as evidenced by the holes in the gear being the same size all the way through. You can try pounding out the pin but I doubt it will move at all so drilling it out is the way to go. Line it up as best you can in a drill press and start with a small bit working up to close to the final size. Once the pin is out you have to press the gear off. Next, you have to line the gear up DEAD NUTS to the pin holes and press it on. Finally, when everything is back together I think you’ll find that a piece of off-the-shelf steel rod fits the pin hole nicely. Cut it a little oversized then pound the ends over like the original was. There, done !!!

Personally I’d chuck ALL your bronze gears in the trash an run a melonized gear. Never worry about bronze flakes in your motor again.

Food for thought … if the pin was tapered, why do they peen over both ends ??

Can you buy a melonized gear with a shaft and save yourself the headache of switching them?

Hughe’s lists them but was always out of stock when I needed it. But well worth the extra few bucks if they have them!

The gears they were using were from crane so I don't know if they're available since they went out of business.

Getting a gear from Hughes was no problem, getting one on a shaft was the issue.

I've replaced several stock gears on stock shafts with after market brass gears, CRS on which brands gears right now.
Same thing on H.P. shafts with iron or stock type gears, I measure the depth before removing the original gear and reinstalled the new bras gear to within .008 of the original depths I never reinstalled the pins, none of the ones I replaced acted up in any way, I'm pretty sure that the press fit is more than adequate to hold the gears on their permently