can't tell, but it looks like you may have seal positioned wrong - end-on it's sort of a teardrop shape, the rounded part of it should sit in the rolled edge of the trim piece, the 'flap' part sticks into the light opening to make the seal
this pic looks like the round part is against the light
it's a pretty tight fit, and if you do have it wrong way round it would probably be toooo tight - also when you put the hook in the slot at top you will have to press it down to get it to seat
all the way in, make sure it's pointed more down than back ... on my bus ones, they almost 'snap' in when pushed down and on
Bill
