still scratching my head on this one

What, pray tell, made you pick GM?

One thing, look at the arch he's got into those springs. That thing can NOT possibly be stable.

oh i'm just shooting in the dark and ventured a guess...i know alot of old street rods ride on S10 frames....someone who would do this probably wasn't a die hard mopar guy who wanted to only do it on a dodge pickup frame..lol....but ya, hard telling what it is...and you are correct is looks very wobbley!