let me get this straight
car came with a plate
you installed a 90 degree over top of the plate
then removed the 90 degree and installed the nipple again ?
if that is the case, my money would be on a overtightened plate
(when you installed the 90 degree it overtightened the plate, causing it to leak)
pull the plate of
check to make sure it is true, and that the center does NOT touch before the outside
it may need a few taps with a hammer on a socket in the center
