Look for an early (68 may have been the first year)Rochester Monojet. I've been running one on my 63 for the 2-3 years, other than my tendency to run it too lean it's been a good carb. It has variable jet that you can tweak. I've seen new ones for $75 but you can get the progressive 2 from Langdon for almost that.
Larry
68 C20 327 daily driver
63 C20 292 Camper truck
65 C10 ? Custom Cab AC,PB,PS,$flasher
