Thank you for your reply. I found a Zenith 228 228BV11 for $50, good rebuild able and complete condition, was in contact with carbking twice on the phone yesterday, and he said it would be a great carb for my stock-built 261. I verified the numbers as well on the dime-size tab on the top of the carb (11963). I will pull up the links that you posted and read more, thanks for your attention.