I've replaced the rear seal on a Chrysler using the method Amervo describes. The Pontiac shop manual explains the two part neoprene seal for repairs also with the same procedure. Is the BOP seal a different type of seal that is more difficult? The chrysler one I replaced years ago was two pieces. With the rear cap removed, it just slips 180 degrees around the crank and it's out. The chiltons for that vehicle said to run a screw into the end of the seal to give something to pull on. It wasn't necessary.

Is the BOP seal different from this?

I've had two vehicles delivered new with the rope style seal weaping. The first was a 68 Firebird. I wouldn't recommend the rope piece for repairs. I doubt it's available anyway.