what did i buy?

[neba]

new to this forum,could use some help.after waiting years for the right truck at the right time, i purchased a 69 longbed c10 a few weeks ago. everything was looking good till i noticed in a parts book that a 1/2 ton 2wd should have rear coil springs. mine has 5 leafs. this seems to match a 4wd. my concern is that the cab doesnt match the frame. would this be a title problem that could come back to haunt me? i found some numbers stamped in the frame below drivers door. 33935807-472 and 7-31-7. do these numbers have any meaning? should i be happy the truck looks nice or did i buy a problem.