Ok, with help from KC people the 65 C30 is at least running again.
Unfortunatly, I think that all the varnished gas that was run through the engine (newbie mistake) has done more than just foul the carb up.
Took the truck out on a decent run this evening and I will list the things in order they happened....
1) In third gear, at steady throttle, she surges just a bit. A little of that hesitation that I am starting to hate comes through. (Put her up into fourth and she seems to smooth out a bit.)
2) Tried to down shift as I approached a stop sign...from fourth to third. (Done this many times on other manuals.) She bucked and backfired. That was a suprise as she never did that on the test drive the day I purchased her.
3) Later as I let the engine take her weight on a down hill, the same thing. I clutched to avoid more backfire.
4) More hesitation and surging in third gear at steady pace, so had her in fourth at 25-30mph
5) Then I took her out on highway and up around 60 she does the same hesitation/surge in fourth
6) Then as I took my foot of accelerator for a car that was slowing ahead of me, she backfired as the engine started to slow her down. (I clutched and took out of gear at that point.)
7) (Unrelated to above, I think) She sounded like she blew an exahust gasket or something about that time as now I hear exhaust right up in engine compartment and not under seat like I did. (Dark now, haven't looked to see.)
So...all of that. I am thinking there is more of this nasty tan gook crud burnt up or plugging something? (This is the stuff that was pulled out on sending unit, was in gas, and was cleaned from carb.) She idles fine still. Wrenchbender said that the engine sounded fine and I was just being fussy about the tapping noise.
Am I looking at major surgery here? Or is there something I am not aware of...(which is most likely).
Dave