yellowsub54,

Have you posted/attached photos of your Z-series GMC?

I have one also (3 window cab, 270 engine, 6v positive ground). It is one of tragedies of my laziness. Mine is finally all painted (all the parts are painted, but not all are installed) and it has a new (installed) 16' ramp system (19' flatbed). I have been worthless in dealing with my trucks since I moved to NC more than a year ago.

Let's see what you have.