Unkel Gilbey: You are correct that the early tankers available to the public were usually cobbled together and not too reliable. Those were the only ones I had any dealings with and most of those had op-rod problems (scraping on front end of stock or barrel flange.
As you said, Hatcher's Notebook is good reference on the Garand during early development. Julian Hatcher also wrote "The Book of the Garand" which goes even further and is a great reference book.
Oleg, sounds like you got a keeper, that's great. They sure are a lot of fun to shoot, aren't they?