Re: M1A bedding question
I got my M1A early in the life of Springfield Armory. 1977, and it has a 4 digit serial number (0068XX). Back then all the parts were military surplus except for the reciever, including the stock.
So my stock came with the cut out for the selector switch, but SA just glassed it over when they put the rifle together. So you had a nice walnut stock with a small section of glass where the selector switch cut out was.
I would just fill in the whole with glass, mixing enough color to match the stock as close as possible.
Having said that, now comes the mean part of my post. In using wood stocks, glassing doesn't really do much as they are acceptable to attracting moisture, changing everything. When wood is used in making NM M14/M1As the stocks should be impregnated with sealent to keep moisture out.
Something that would help a lot, in building your buddies gun is the NM M14 Accurizing guide put out by the AMU and NGMTU in the National Match Armor's course.
I have that guide in .pdf format, if you pm me with your e-mail address I'll send it to you.