Yamaha DTXpress/DTXplorer/DTXtreme

Hi,

First post here. I've not had my kit for too long and now want to 
assign one of the pads to a ride cymbal and the ride to another crash.
I've searced through the messages on this board but am having trouble 
finding the correct set of commands. 
I'm sure this question must have been asked before, can anyone point 
me in the right direction?

Thanks

Paul