I have an '04 P.2 and I want to add a granny gear and a bashguard. Can I just buy the gear and bashguard, or will I have to buy the whole thing (http://pic10.picturetrail.com/VOL326...6/66023746.jpg)? The P.2 comes with the Truvativ Hussefelt crankset, but with just 1 38t chainring. Thanks.
Depends on the crankset. If the ring is bolted not rivited to the crank arm you should just be able to undo the bolts and fit a bash guard. As it currently has only one ring the bolts might not be long enough so you may need a longer set.
You will be able to fit a granny if the crankset has the threaded holes for the bolts.
Your current chain guide will no doubt not work with two rings so if you need a guide be prepared to replace it with a duel ring version eg e.thirteen drs