Help with Avante (strange) Pfister shower valve

[DIYGST]

Hi, I am working on changing the cartridge and new trim kit to the pfister valve. It originally has plastic threads sticking out for the round trim to thread into. Anyway, I broke off some of the plastic while removing the trim. The plastic sleeve is held by 2 screws out of the valve's 4 holes. There is a slot on the top and bottom which looked like the pfister valve I have seen. The valve is single handle obviously and you pull out to start water then adjust.

so far I have believed this is called avante or 0x9 valve, I ask pfister and that one person I got on the phone said it doesn't look like our valve because of this plastic sleeve.
The handle cap for the valve and bath overflow says price-pfister..

Anyway, as I said I am trying to replace the trim kit, so the plastic sleeve needs to be removed. I am having trouble with the collar nut being tight. I put some PB blaster, no luck. Before I packed up for the day I put some vinegar into the top slot hoping it may help the threads free from corrosion.

The valve isn't secured to anything, so I was trying to be careful with the torque and used pliers to hold the valve by gripping the plastic sleeve. I shouldn't need to turn off the water until I'm trying to pull the cartridge right? Anyway, thanks for any help you can give or please confirm the brand if you know.

Thanks!!

 

[FullySprinklered]

Looks like a baby seal looking through a hole in the ice. Have you tried hitting it with a club?

 

[Sponsor]

 

[hj]

I am not sure if my reply was deleted or you also posted on a different site. That is a Pfister Avante valve. You unscrew that cap, put the screw into the stem, push the stem in and the YANK it our swift and hard. Repeat as necessary. What is the 'plastic sleeve" you refer to?