A pair of Kicker L7s and a ZX1500.1 is a decent enough set up, but there are still alot out there that can do about the same if not better, so this kinda comes down to the amount of space you want to use up in the back of that truck and what you're listening tastes are (myself and a few others on here still do not care for the sound quality of a square sub compared to round, but that's opinion)... And proper ported enclosure for a 12" L7 is going to eat up a ton of space in the back of that extended cab (roughly 4.5 cubes total per sub).
Now you have to keep in mind budget... How much are you planning on spending? And are you buying from ebay (online) or from an authorized dealer?
I ask these questions because as great as some deals are on ebay (and other sites) they are not authorized dealers (although they may say they are) and you will not get a factory warranty, so keep that in mind when buying (that's just my general warning I give to everybody, as I don't like seeing people get burnt if they do have to have repairs or replacements done)
