Not meaning to start an argument/discussion, but, the dual Rochesters used on either of my old 261 engines have also been running fine/untouched for over 20 years. They have very minor fuel stains over those years
Clean/new gas always, clean gas tank and fuel lines, clean air filters, and clear-view fuel-filters in two places. We balance and adjust the carbs quickly using the vacuum gauge adjustment/balance technique (every few years).
As I have always posted, those two Rochesters were/are "too much carburetion" for the engine - the truck is no longer mine. I now have a single larger-than-stock 2-barrel from a GMC 302 (with adjustable jets) on my 1960 261. No fuel stains on this carb (5 years of operation).
