Just thought I would renew this post to let anyone interested know the resolution.
I finally gave up on replacing the valve connector seals in my sensors and called TST. The tech rep was very nice, offering several ways to do the job. Nothing worked, so I gave up and sent all the sensors to them. The service tech called me personally and explained that one sensor was bad and he would replace it under warranty. The suprising thing was that none had a seal. Apparently the factory never installed them! So, it is no wonder that I had problems extracting them!
They are working again, and I had to pay around thirty bucks for the work they did.
I have to say that the reps were great to deal with, and I feel that TST is a good outfit that provides decent support for its customers.