Hey Snowman , I Googled that number and it came back as a "base" used on a 261 Chevy, Rochester Monojet , do not know if that information is correct but a picture is worth a thousand words. Try copying and pasting this url into your browser and see if you can find it within the site. Hopefully Jon (Carbking) will see your post and chime in.
http://www.carburetion.com/r1.asp#R1M
