I have tried blue on the grip bushings and green (low strength) on the grips screws, with little success. Sure enough the bushings always loosen up before the screws and I would end up destroying the bushings.
Now I use a SMALL amount of blue locktite on the bushings and nothing on the grips screws. As said, the #60 O rings work great. If they are too thick, cut them down using a razor blade. I would rather have the grips screws loosening up rather than the bushings.
I'd suggest you pass on any loctite on the grip screws. As noted above, O-rings will do the job and allow you to remove the bushings easily without messing up the threads or slot or hex head. Breaking blue loctite loose is via force. Grip bushings and slot heads are fragile enough without adding to the problem.
I use BUNA-N O-rings in the 5/32" ID x 9/32" OD - 1/16" wide. I get them in packs of 25 at Small Parts, Inc., which is also a good place to find those "hard to find" screws of all kinds. http://www.smallparts.com/