I'm new to the IDI world and have found that parts are becoming obsolete. For example, I have the belt tensioner with the support shock (1 of the 3 variations ford created for belt tensioners on the IDI). Ford no long makes these parts as they are "obsolete according to two dealerships and the aftermarket stuff from Autozone/Napa/Oriellys/Advanced Auto don't fit. What do you guys do in this situation?