Jon,glad we can agree,lol.I use the 1904 Holley's to replace Rochesters cause they are inexpensive and readily available,and are a worthwhile improvement.The other carbs you mentioned may be better,but they are much more costly.I use the metal float covers,just don't trust a glass bowl sitting over an exhaust manifold.The later 1920 Holley's used on non emissions Mopar slant 6's are a one piece design,cheap and easy to find,but need the idle restriction drilled out slightly(.001)to eliminate an off idle soft spot when used on a 235/261.The end result is a smoother running engine,more power and improved fuel mileage.Of course ya need to rework the air cleaner throat to fit on the Holley.
I'm not that familar with the old Strombergs,but I believe their strong point is the easily changed idle and air bleed jets,that's if you have a supply of jets or can make em.
It's been my experience,that the single bbl carbs originally intended for trucks have much larger power valve restrictions that car carbs.So dual car carbs will generally work better ,as in not over enrichening the mixture at wide open throttle.
But like we said,finding matched carbs can be difficult unless a guy wants to spend lots of time with pin drills,soldering up restriction jets and road testing different combinations.But actually,you'll never know if an engine is running to full potential without dyno or road tests when doing carb swaps.
