I wouldn't use loctite on manifold studs, done up right they never come loose, the problem is in getting them out, they are usually seized solid.
I did mine and used nickel cote on them - fingers crossed I'll be able to get them out whenever I need to without any drama's - 25,000km later and not one has gone loose on me. I periodically check them and cannot even get them to move, so they are solid as, but hopefully [with the nickel cote] not seized.
But yeah SK recommends loctite - I think its asking for trouble next rebuild time [and I don't often disagree with him- son of rajab knows he's got way more experience than I'll ever have] - so its your call.