Hi. I have an old Dodge B-2-d pickup with the hydraulic hoist and wooden box. I was wondering what could be swapped into it for engines because I'm thinking of restoring it and modding it a bit. It's a 1950 and had the flathead 6 As the source of power. I was wondering if a cummins 12v would fit without too much custom fab. Thanks. Or any other engines that would fit without too much modification.

 

Anything that old is going to be all you buddy. We would love to see pics and hear about the project, but most of us on here have no experience with anything that old and oddball. That being said, with a welder, torch, some cash, and a little imagination anything can be done. I would be surprised if you couldn't figure out a way to make a 12v fit. Good luck!

 

I have a fair bit of experience with Chevys from that era, but no Dodges, unfortunatly.
The project you have in mind is not one that is going to be like everyone elses. That is great, because it will be unique, but bad because you are forging new roads, and there is no map to get you where you want to go.
If you are looking for a kit to make it happen, I advise you to pick a different project truck. That being said: Trucks of that vintage tend to have a ton of real estate under the hood and lend themselves well to big engine swaps. As wombat said, a welder, torch and cash will make anything possible.
What condition is it now? Farm fresh? Parked in a field/barn/grandmas garage? I would love to see a pic no matter what condition it is in now. I love those type of projects.