The two seals are not interchangeable...
You most likely have a steel "bullet" for the trans speedo gear, which requires the metal-clad seal, similar to, as you say, the wheel bearing seal, or a trans front or rear seal(only a LOT smaller). The Aluminuminum "bullets" use the soft rubber type seals, with a small, circular wire clip to hold the seal in, which will not seal in the steel bullet. You need to either obtain the correct metal-clad speedo seal, or get a new steel bullet.
If there is a transmission shop in your area, they may have the correct seal in stock, or possibly a new steel bullet with the seal already installed(new bullets have the seals installed when you buy them). The metal-clad seal itself
might be avalable at a NAPA store, but I'm not sure.
If you cannot locate the correct seal, P/M me, and I'll send ya a new bullet.
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Joel Adams
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