I had the same dilemma on my previous 98 XLT while I was rebuilding the transmission. I ended up replacing the seal - Actually, I ended up replacing the seal 3 times because I kept doing it wrong and it would leak like crazy. Learn from my mistakes!!
The P/O had installed the sleeve upside down (with the flared end facing rearward), and I assumed it was correct when installing the new seal. Basically, with the flared end aft, the seal and the sleeve have to be installed together as an assembly - there's no way to get the seal on if the sleeve is installed first. By installing the two parts together, the sleeve was pressed up against the seal. When I started the engine, the sleeve ripped the seal apart and it leaked like crazy.
Moral of the story: If you use a sleeve, install it with the flared side forward.
As it turned out, even after I removed the sleeve and polished the crank surface, I installed a seal WITHOUT a sleeve and it only weeps oil, not a significant leak. I used a teflon seal. Rubber seals should be coated with oil when installed, teflon ones specifically say to install dry.