On first pass, ~$300 for the Holley 2300 and $450 for a webber. Like them both and have run both holley and webber, 4bbl Holleys in US iron and D481's in my porsche powerd 58 vw. In the mean time we found the problem, fuel was dribbling out the venturie's during low idle causing it to run very rich with the idle plate closed. Just pulled it apart, ran some copper wires and carb cleaner thru them and reassembled, stopped one side, took it apart again and recleaned it, reassembled, no more dribbles and it idles nice and smoothly now.
Oh, alternator died last nite, quick $80 for that. Next we need to pick up a vapor cannister to keep the carb from sucking up any more dirt.
Did a flush on the cooling system on sunday, noticed a leak around the top bung on the rad, figured to go for it and pulled out the old propane torch, resoldered it and no more leak...for now. But it needs a new rad, this looks like OEM and even after the long flush, backflush kit install and backflush there is still alot of crud in there choking the core but at least it stays at 190f rock solid.