Thanks for that! Shows some of the trade offs nicely.
The CAMVATE female Rosette I found is thinner than the one you show in these photos and will mount to the RRS clamp at an offset, which can be compensated for by positioning the clamp higher on the L-bracket:
In the event that it spaces the grip and such too far from the 907x camera body, I can use it to determine the proper angle and than make a very thin bracket to bolt the wooden grip with minimum offset to the clamp. That eschews the adjustability, but basically once I know precisely the range of angles that willl work for what I want, I'll likely only rarely need the adjustability.
The LH grip I ordered is the simpler one ... it's just the male Rosette on a simple pedestal that is bolted to the grip without the plate with multiple mount points as in your photo. That means it should be lighter and easier to make a simplified replacement for in the event that I want to reduce the size and weight of the assembly.
It seemed evident to me that the closer and tighter to the body I can place the grip, beyond having enough space for my fingers, the better it will be. Getting there is the tricky part of the whole endeavor...
G