If you have the 5/16" convertor bolt holes, you have the P5007378. Fits a 426 8 bolt crank. For use with stock type or mild convertors.

P/N P4529752AB would be the same thing but with 7/16" convertor bolt holes. Fits 8 bolt 426 crank and is for use with B7M or other aftermarket convertors.

The convertor attaching bolt holes should be on roughly an 11" circle.

Sid