Getting ready to change my carbine buffer tube to a rifle length tube..... Its a cmmg lower that came from the factory with a carbine stock, does cmmg use red loctite? I want to make sure that I have an idea of what I am up against.....

Highly doubt if they use red. Check for staking and use a good wrench and secure the lower.

Start taking off the castle nut with the lower secured properly even with the nut staked it won't be too terribly hard to get off.  If it feels like it is taking some serious work then apply heat.  Heat up the nut and then give it another go with your wrench.  There isn't much to it at all.  I am sure there are piles of videos that you could look up.