Ramp truck questions

[GR5]

Hello Everyone,

I'm interested in building/buying a ramp truck to haul my vintage race car. I have a few rookie questions that I haven't been able to find an answer to.

Can I make a ramp truck out of a C20 or is that silly and I should really start with a C30?

Are all C30's duallys and alternatively, were C20's ever duallys? I'm assuming the answer to the second question is no, just making sure.

Did the C30's come in different wheel bases? If so I assume the longer wheelbase is preferred for a ramp truck?

I know these are novice questions, but I'm just getting started so I apologize.

Thanks,

Mike