My buddy has an automatic turbo caravan and needs to get the rpms down when cruising on the highway. He refuses to install a lockup converter, and he doesn't have any taller tires at the moment. I remember the mod being transfer gears from 79-83 Omnis but there's like none of them in the junkyards around anymores. Is there any other cars the same transfer gears might come out of? Anybody I can buy them from?