Carter BBD differences

Dave999 said
there is nothing to stop you taking the rods jets and little jet spring from one and putting them in the other....
the wrong carb with a decent base, none leaking throttle shaft and a bit of linkage you don't need will still work better than a worn one, just configure its jetting as per the orginal.
block off any extra vacuum connections you don't need.

warped air horn and worn out base/throttle shaft bush area is usually the BBD problem.
or missing parts.......like the clip for the fuel bowl vent.... necessary on the older style for them to be RIGHT.. :) .... yours will have a tin top if its 1970s, and this won't be a problem for you, accelerator pump rod through the side, rather than a slide through the top of the bowl.

You can get the linkages cut off, the throttle removed the holes bushed and it all reassembled, with the linkage welded back, if this is the problem with your old one.

Dave

Thanks for taking the time to write all of that out. It's an interesting option. The 8001S carb that's available is new old stock and listed at $399, which isn't cheap, but I'd be willing to spend it if it was suitable to use as is. At the listed price I doubt it will sell quickly, so I think I have some time to consider your suggestion. For obvious reasons a suitable 8000S would be the preferred option. I missed a new old stock one that came up on eBay by about a week awhile back so now I'm doing a daily search and hoping to get lucky.