I ended up using the original linkage. I think I had to turn the carb to make that happen. They can be had for pretty cheap from Tom Langdon at
http://www.stoveboltengineco.com/aca...asp?catcode=33
Tom was an engineer at GM and played a part in developing the 250. Whether you're trying to hot rod a 250 or just make it driveable he can help. I would just call him. I think I needed a 1-2bbl adapter and the carb.Tom has a linkage, but I didn't particularly like the appearance of it.