I'm just going off of the frame info I could find at the heritage site. It showed extensions on the 4100 frame. I've worked with 3800 frames and a 6400 frame. I know the two ton trucks have the longer frame horns with those side brackets you mentioned, but I wasn't real sure about the 4100 frames. I have a line on a cheap complete 3800 frame that I'm thinking about using for my next build which will use a big bolt front clip and a 9 foot bed. I'd like to use the big bolt bumper as well, and hopefully use factory parts to mount it.


Liquidated my projects
Now looking for a decent '47-'55.1 3100, 3600, or 3800