Steve, I have no idea of what vendors your talking about with the aftermarket alternators, But I think it's a great idea. So from now on, The Delorean D150 ( 150 amp ) alternator, sold by Special T Auto.com will come with an extra bulb with a letter of explanation. It already comes with a longer bolt and a locking nut and heat resistance fiber tubing to cover the wires and a 3 year warranty. Thanks for the Marketing Idea. John Hervey http://www.specialtauto.com/alternators.shtml << This problem has come up a lot in the past. Maybe the vendors who sell aftermarket alternators designed for the D supply a bulb with it? The bulbs are 20 years old and one can only guess when they are going to blow. Could you imagine getting stuck on the side of a road because of a bulb?! >>