Fixed Up North

Before I buy a pair to see for myself, could someone please tell me if turning a mountain bike crankset into a one chainring set up is as simple as popping the extra chainrings off and using some single stack chainring bolts. I've done tons of times with road cranks and old moutain bike cranks, but the new(er) crankset with four arms look like there might be something else going on there. I'm thinking about picking up a used LX or XT crankset to use for a single speed mountain bike. Thanks.