The grips are interchangeable.
Finger grooves on left side, Not a lot, but makes it a lot more comfortable. Probably took me 1 1/2 to 2 hours, start to completion, including lightly sanding the entire grip body and adding some finishing oil. I had previously done a little work on the right side, just under the trigger guard, where my large finger wraps around.
Jeff, I had to stare to find your mods, they blend in so well.