Replace shower handle on weird shower stem

[meatheadmike]

I'm trying to replace my nasty gunked up shower handles with some new ones, but when I took off one of the handles I found they have some weird looking square stems (see picture), instead of the spline looking ones that I've seen before. Is there anyway I can replace the handles without having to change out the stems?

Also if I do have to change out the stems, would I be able to do it without having to change out the entire valve/pipes which they connect to? I ask because they way they connect into the wall doesn't look like threes a way to undo them with a wrench or something (see other picture).

Redoing the plumbing in the wall seems excessive just to change out a stupid knob... is there any other way? Thanks

 

[meatheadmike]

Upon further inspection the front of the top and sides of the stem have these holes (see pic) there are 3 of them total.. perhaps for removal? Any help or advice at all would be greatly appreciated.

Thanks.

 

[Mr_David]

Those are just adapters for "fit any thing handles kits".
Holes have set screws. Use an allen wrench to remove or dill them out
If you can unscrew them, just loosen them up and the square block will come off.

It is most likely that the set screws damaged the splines an the stem.

Good luck with disassembling the stems from the valve.