Input on a bent frame please

[oldsmobilekindofguy]

There is a bit of a bend in the frame of my 67 c-10. The bend is right in the middle under the cab on the drivers side but only on the bottom rail. The frame is otherwise straight so I wasn't going to mess with it but I am switching to a th350 and the crossmember goes right where the bend is I believe.

I was wondering if anyone had any good ideas for straightening it other than heating and hitting. I was looking for a clamp or something to get it more even that with a hammer, but couldn't really find much online. Thanks in advance, here is a picture of the bend.