I have one gun that had all of this done, yes I am in the process of restoring it.

Greener Pigeon grade 12ga

Received it with:
1 Hot blued Damascus Barrels (yes ribs loose)
2. Beavertail forend
3. Adjustable comb, yes original stock cut for this "feature"
4. A Morgan adjustable black rubber with aluminum recoil pad.

I don't think there was much more you could have done to try and ruin this gun....