Need help identifying old Delta Shower valve

[Ddmcam330]

Trying to repair leaky shower head.
Need help identifying and taking apart this old Delta shower valve.
Got this far, but no clue now.
Can anyone identify this??

 

[Terry]

This chart helps with Delta

Depending no the year, it could be an RP19804

 

[Sponsor]

 

[hj]

The essentially all look the same when installed. You have to remove the core to check for the differences.