I have a MSD Pro Billet Dist. 8366 and low and behold inside of it was a genuine gm module. I need the part #, the number on it doesn't cross. 409 9f26 on the back it has 409 4h15-03 MSD does use the GM Module in thier 8366 Dist. Not very good customer service from them. Here is the e-mail I got from them.. Dear Sir; We don't have the GM part number, but the one we use in our distributor is a stock unit. Any local auto parts store can get that for you. Thank You, MSD Tech Nice to know the year and application!!!!!!