Question: can a panel frame be used under a truck?

[Eagletucky]

Guys,

I picked up a '66 panel wagon last week.

I already have a short bed truck and was getting ready to swap out the crossmember and rear end from a 78 truck. I was thinking i might tear the panel to its bare frame, swap out the crossmember and rear end from the'78, replace all of the bushings, bearings etc. Paint, powdercoat. go through everything. then once that is done, transfer the body from the old truck to the panel frame.

My actual question is, is a panel frame the same as a truck? Is this swap even possible?

Thanks in advance,