man that is the exact 5.0 i have been looking for for the last year and i hate that it looks soooo sweet cause it makes me want mine even more lol, good job man uve got some sweet cars
just make sure you hooked the connections back up cleanly when you installed the cai, the mafs can cause the car to do some funny things, make sure you didnt put the mafs back on backwards, i have heard of that before
all i would do is send him the offer of $250 cash and let him sit on it for a bit while u continue looking, if he is ever gona go lower he will call u back within the week.