the bottom is not really much of a problem as it's usually sealed by all of the crud build up, so much so you usually need to pound it down into the block to get the intake off, which is sometimes handy as the crud will hold the tube down, oil flows though that tube too so it's clean it's probably not leaking, one tip to get the top o-ring seated is to twist the tube while pulling up and it will pop into it's groove
all america wants is cold beer warm cat and a place to take a poop with a door on it