Wyle E Coyote, How big is that travel trailer you want to tow?

Modern is a relative term. I have a 2003 1500 Dodge sitting here, everything on the front end of that 1500 is way more heavy duty then most of the 72-93 stuff until you got into the 1 ton stuff.

When Dodge came out with the new designed 1994 trucks, everything older became obsolete. Finding parts for pre 94 anything is getting harder, and will only get worse. Most of the aftermarket simply quit making things for the earlier then 94 trucks almost overnight. If you truly want to upgrade your 66 pickup to something you will be able to get parts for, I would look for at least a 2001 Dodge (2001 was another chassis update and is almost 18 years old now) and swap out the chassis. The modern Dodge trucks are at least consistent in parts usage, but it will probably be a pretty big undertaking. You would be putting your cab, box and front sheet metal on the newer frame/chassis.

If you want more easy, locate a complete 73-93 heavy duty 3/4 ton pickup chassis, and swap all the front and rear suspension and brakes over, then hope the next time you need parts, they are still available. Gene