Ghost ring and fiber optic pin.

Sorry stuffed up.
Its a picatinny base.
Only dove tail mount I have left is the one piece gamo base, unfortunately I'm not prepared to cut the scope mounts off that.
Still food for thought

Here you go Pete.
Followed your idea and cut the plastic end off barrel pulled the air chief rear sight apart.
Took out blade. Cut bottom of ring flat, cut little piece out of bottom left hand side as needs clearance and have epoxied it to the blade (waiting to dry) between the blade and the bit behind.
Should work and will give a adjustable ghost ring when reassembled.
This is proof of concept, so I'm not making it tidy just slapping it together.
Once I find the that bass again I'll put it on top and see how high it sits.

Hey Pete, pulling apart a red dot for spare screws and bits and pieces.
Would this be of any interest to you. Had it on the gamo I think so is 11mm. I imagine that central hole is centered and with threading would take a ghost ring rear post.
Was thinking about going down and get the air chief out of the tip and ransacking it's rear sight and replacing the rear blade with a washer dremeled to fit, but though see if you wanted base first.

ja, I have such a nice cheek weld onto the comb with the current open sights, Id want to keep the ghost ring set up at exactly the same height as the current rear blade.