If you are putting in Fel Pro'*, please make sure the part number has a T on the end of it. This will ensure they are the aluminum frame gaskets. Otherwise, you'll end up doing them again. GM Dealer is the other source for aluminum gaskets.
As for the torque and sequence. LIM bolts from the factory should be torqued to 13ft lbs. Start in the middle and work your way out, alternating front/back of motor. Also use a ptfe sealant on the LIM bolts so that they don't wick coolant and oil up onto the top of the LIM.
When using aluminum gaskets, I automatically increase the torque to 15ft lbs.
00 Regal GS: All kinds of cool stuff.