in tank. They're not hard to install at all, I did it in a friend's driveway right before we went to the track. all Honda/acura tanks have access panels on the top that's accessible under the rear seat/trunk panels so you don't have to drop your tank. I just have the walbro & a generic adjustable fuel pressure regulator & I've got plenty of fuel flow. i'll eventually get a rail & injectors, but for now i'm fine.