Cat d5m angle cylinder seal kit. I can't get the blue seal in the end of the cylinder cap
Here is some tools and videos
Strong hands and lots of work.
If it was the old style buffer you took out , did you get both rings out of the groove? The outer is hard to see if you don't know it's there.
Yep there was another ring in it.
That'll get you every time...... Another tip for really difficult seals is to put them in some hot water before you try to fold them up for installation