Forget F-100s...
The last year for F-100s was 1983.
I like F-350s+ (maybe a little F-250...)
I know where there is a NICE '75 F-250 4x4 in Riverside, I tried calling the guy, but he never returned my call, I'll call him again tommorow.
Here's a picture of it...

 

Well, it looks nice. But, since your young, presumably don't have a job (you've never said anything to the contrary....), I say F-100. I see more parts, and after market for them, than the others (my family has a '75 250 and a '76 350). Plus, I'd imagine you could drop the bigger motor into it, if you truly desired... Just one farm boys $0.02.


Edit: I get made fun of by my NM family for have an F-100 with a "Baby" "little" 302, and not having the bigger trucks with bigger engines. Then again, they're not much use when I need info.