Need help removing valve

The chrome sleeve won't budge.
I thought I could just leave it and remove the entire valve. When I removed the two screws holding the actual valve to the part in the wall the valve won't come off in fact doesn't budge???

I think its Kohler as that is what the trim pieces say. I bought the Kohler valve replacement and it looks like it will fit perfect if I can get the old valve off.

I have pictures in the pictures you will see a c-ring but I have removed that after the pictures were taken.

It has been awhile since I have worked on a Kohler, but with the two heavy Phillips head screws removed, one on the right and one on the left, the front should come off, along with the temperature cartridge. Try carefully convincing it with a rubber mallet.

Thank I will give it a try!