OMC V8 Prestolite BID Shift Assist Module | CDI 123-7571 CDI Electronics 123-7571 Shift Assist Module OMC V8 Prestolite BID Shift Assist Module For OMC V8 5.7L GM, 5.0L Ford, and 5.8L Ford engines with Prestolite BID distributors Replaces OMC 987400, 987564, 987571, 987700, and 987876