the were two different sized pilot bearing holes for a 429, pre`70, and later..1.375, and 1.850 sized holes. The one thats 1.375 is the same convertor used on 289-302-351-400-and 429 with a C6, with the 1.375 hole. The 1.850 hole was used on 390-428, and a 429 with that size hole and C6. Both these convertors are sold by the major converter maufactures, and I have a B&M C6 11" Holeshot for sale for the 1.375 hole crank. $100 There was no 1 1/2 hole crank, try to measure it again.
Posted on May 2, 1999, 6:22 PM from IP address 209.240.200.88