I ordered Low Talley LW's for my Borden Timberline. Cheekweld is perfect but the Magnification wheel is touching the mount. The scope won't slide back in the rings any farther. Will Mediums work?

Yes, the mediums should work. Not a great pic but these are lows and I just barely get clearance with this scope so figure the mediums should be OK for you.

Is the front ring reversible and still maintain proper eye relief?

It is very easy to modify that ring/base a little with a file. Take a little off.
Access to a mill even better!

They are both turned inward

👍

I’m not 100%, but I think Talley adds height to the bottom of the base, not by increasing the distance between the top of the base to the bottom of the scope tube. If so, your magnification ring is still going to be touching the top of the base, but the scope will just be higher up.

I’d call and ask.

Just take a file to the base. I've had to do that on a number of them.

This.

Dont order mediums, just take some material off the back of the base so you can spin your knob.