Glass tops have a heavy vinly strip that can be cut
to exactly A) the intake and output area of your
filter, or if using a canister filter drill holes
for the intake and return. For cutting vinyl use a utility
knife remember make the opening no bigger than
needed.on full canopy top its the same thing except you'll
need a jigsaw or scrollsaw to cut the openings
AS for the opening part of the lid or top make sure
it fits well and add weight to it fiberglass screening and silicone
work wonders also -Anne