USMCGrunt, I have used Devcon products for quite a few things but never a bedding job. It might work! Gale and the MCBROS will certainly bed your rig for $$ as well as Fulton Armory etc. I know that Fulton will do an amazing bedding job "for a price" but this is one of the first tricks I ever learned on a M-14/1A. Get the books, a rifle vice like I have!, and try it with a wood stock first.
On your rifle, you must pay attention to the undercuts on the metal. A Garand is much more unforgiving than the M1A but... A Dremel type tool is very helpful here to make the cuts and recesses here. A pinch of modeling clay and plenty of mold release and you are close to home my friend.