It only starts with starting fluid, but then seems to run great. It dies hard when put into gear, and has a serious flat spot off idle. So I check the timing. The thing must have been advanced a tooth due to how far advanced it was! I tried to adjust it, but the closest I got was about 10 degrees. So I moved the dizzy one tooth and it wouldn't run at all!
It even tried firing up through the carb a time or two on the restarts or on accelleration. 
So I switched the brain box to the electronic ignition to see if it would help. Maybe a little, but not much. Cleaned off the contacts in the cap (a bit corroded) but that didn't make a noticable difference either. Plugs look ok, though a little black, like it's been running rich. Tried adjusting the carb, but I couldn't make anything better.
So I am thinking that I need to get this thing back to where the settings should be, then diagnose from there. So, does anyone remember what the air gap setting is for the ignition pick-up? What about the carb? I can't recall how many turns out the air/fuel mixture screw should be. The carb appears to be a recent part, and it has great fuel pressure. It's become painfully obvious to me that it's been entirely too long since I played with a 6, that's for sure! All my trucks have 440s.
I know this truck was roadworthy just days ago, as I saw it being driven many times in the last two weeks by the previous owner. So it can't be anything serious, or at least I'd like to hope so. Thanks in advance for your help.
I'll take them all over there on thursday and see what else I can figger out. I'll let ya know what I find! 