i went to the website and fouind this carb and part number
http://morrishobbies.com/product_inf...eec2f38f456823
the bolt pattern is different from that i have with the rear intake.
But good to hear the OS may work with my engine. 15mm is a big and hopefully it matches what i have in there now.
I'm going to try this set up out and see how it goes, thanks for your reply!