66 d100 dodge my son is considering, your thoughts

No offense meant, but I never liked the styling on those first-generation D-series trucks very much, and it is very difficult to find parts for them.

I greatly prefer the styling of the third generation D-series (1972-1980), and it is a better, more refined vehicle in many ways, especially after 1978 when the steering was revised. Parts for the third-generation D-series can still be a problem, but not as difficult as finding parts for the first-generation trucks.

And third-generation D-series trucks are dirt cheap!

They were one of Ma Mopars styling flops for sure. The stepside was a lot nicer. It wouldn't be a resto, just a drive it like it is with a little body maintenance.