Heavy duty work truck

[72kool]

Since coming to a roadblock with my build, I've had some time to think and in that time my needs have changed some.

I want to ask your opinions on what you may do on my situation. The pickup I have is a 72 GMC C20. I need a truck that can haul two cars frequently and a few times a year, haul 3 cars. Total load weight will be 15-18k pounds and over long distance of a few hundred miles.

Also want to go 4x4 while I'm at it because I sold my 4x4 and where I haul these cars, it is a must.

My plan is to forgo the current chassis and body swap to a full setup. I was thinking of finding a wrecked ram 5500. What would you use? I also considered a c50 chassis but they are not highway friendly and also not 4x4. Any experience with this and what would be a good setup to look at? Fab work is no concern. Want to hear any and all opinions

End goals are: tow 18k load at 70mph frequently
4x4
Daily work truck