Like D100 said theres a 1.720 bore in the 750 body/baseplate and a 1.750 bore in the 850 body so theres going to be a visable step....but the biggest problem is the 750 and 850 have the idle circuits in different spots in the baseplate and it will not idle/work....you would need a baseplate and body from 850's....Jesse


Jesse & Lynn BIGS Performance Products Building Street/Strip Carburetors since 1974 www.bigsperformance.com