as long as the system is sealed you wont have any problems.
Other than being sometimes a pain in the ass to get to, the only thing that will cost a larger chunk of change is the fuel filler.AS the hose likes to split and the filler spout its self will sometimes have a leak in it.where two parts are formed in the sheet metal
or I have heard a few piss off stories about the sender unit ring not sealing,on the gas tank, that can fail the truck too.
the charcoal canister is the only other costly part.that could be "broken" that would cost a few bucks.
other than that just the vacum line that runs from the tank to the canister is your only other worries.
and of course make sure you have a good gas cap,It it means buying on at the autoparts store just in case your cap fails. so you have anouther one to say "here" with to the smog tech...and if you don't need to , you can just take it back to the store. Better than failing a test and having to re pay etc.
OR you could put a pair of wings on it and buy a "carbon credit"