Heeding the sage advice of the experts, I decided not to mess with it, and instead made a custom tripod pad.
My goal in all this has been to be able to leave a tripod pad on, and still to be able to attach the lens to a monopod or other device without taking the pad off, and also to have something that served reasonably well as a hand holding handle, all without having to screw the pad on with gorilla force. So the upshot is a custom pad with the top milled to fit the lens foot, round corners, and a couple of threaded holes. I have an old fashioned metal shaper whose bits can be custom ground, making it very easy to cut the tapered groove for an Arca mount. The extra length makes it possible to balance nicely with the light D3200. The actual balance point is nearer to the front threaded hole.