PistolRogue - sorry it took me so long to answer - been away for a little while. It is the AMT Lightning stock i.e. - 10/22. I was very impatient when I started the build and basically "hogged out" everywhere in the receiver area because my plan was to build it back up to fit. After doing that, I covered the Hammer in packing tape , covered the inside of the stock with JB weld then stuck the Hammer in the stock where I wanted it to sit. After it dried I just cleaned it up and painted it.
In a wood stock that you want to not paint to retain the beauty of the wood that would probably not work for you. But from what I remember, the Hammer's dimensions are relatively close to the 10/22 receiver (other than some minor cosmetic contours, the mag release, safety, etc.) and with some careful measurements, you could get the Hammer and barrel to fit, then glue pieces of thin wwod sheets to take up the spaces, then stain the whole thing.
I hope this helps and again apologize for the delay