is installing a cai easy?

Depends what kind it is. The ones that mount the filter in the fenderwell can be a PITA to get lined up sometimes. The open element type, or "ram air" as JLT calls them are pretty straight forward.
 
Id go for a March Ram Air... it will do more than a CAI, and I dont think (looking at the pictures) that you have to rip the stock intake out. Less expensive too.

Ive done an intake on my 4x4 and a fenderwell CAI on my freinds 3.8 Mustang. Biggest PITA is finding someone with small enough hands/arms to reach up in the fenderwell and get the filter mounted and tightened... its annoying, not hard.
 
BurningRubber said:
Id go for a March Ram Air... it will do more than a CAI, and I dont think (looking at the pictures) that you have to rip the stock intake out. Less expensive too.

March "Ram" air = vaccuum cleaner...

Avoid it.

CAIs are easy as stated before, just be careful with the MAF palcement if you get one that relocates or has you temp remove the MAF.