Frame differences between Longbed truck and Suburban?

[Tow Me]

Sorry I wasn't clear in my previous statement. I'm using a 1970 2wd long bed truck frame to put under my 1970 Suburban. The plan is to install a new lowered crossmember like Porterbuilt, a rear c-notch, new crossmembers and trailing arms. Once the frame is all done, I'll swap my body over to the new frame. While I build the frame, I'll enjoy driving the Surburban with the static drop on the factory Suburban frame it currently has.

The recommendations above from Frizzle Fry say the only 2 differences are the rear frame sections and the position of #4 body mounts. I was in the midst of getting these pieces and I was told by the seller that the 2nd and 3rd body mounts are different so I would need those too. I just wanted to see if anyone could confirm or comment about changing all the body mounts.

Thanks for the suggestions! I will look at those threads too.