I had mine repaired by vinyl welding. I contacted a couple of local dealerships and obtained the name of the Company they have come in to do interior repairs. Turns out that the Comapny has the ability to do this vinyl welding repair and somewhat match the grain in the vinyl. Mind you, this is NOT concours quality but very accepatble for everything else. The crack I had repaired was in the arm rest of my drivers side deluxe door panel ('68). It cost me a $100 and that beats $300+ for repro panels. Check it out, you may find there are people in your area that can do this process.
BTW: They told me they may also be able to repair the single crack in the middle of my dash pad. I just have not had the time to pursue this yet.
