please help with aquarium repair advice

I  have a 100 gallon (60x18x21) Perfecto aquarium. I have the stand
hood lights etc, and the tank holds water. Consequently I want to keep
it. The tank is about to be re set up after being empty (on it's stand
) for 1 year. Problem is that I notice that the plastic frame has
splits in some of the front corners. (not sure how long they've been
there) Some splits are 1 inch long , some only a few millimeters. The
cross brace on the bottom has a small crack, the top one is completely
okay though. I checked the newsgroups and even called Perfecto to
figure out if this is a major issue or not. Seems that the plastic
frames on the top and bottom of glass aquariums are put there mainly
to protect the glass edges from chips during shipping as well as in
your home, and their purpose is not to hold the tank together. Some
have said that they are cosmetic only and that the silicone is all
that is necessary to hold the tank together---wiith one caveat: that
is, with a 60 inch long tank. I may expect some bowing of the glass.
The cross brace minimizes this. The plastic frame is important for
this reason. Nobody eg Perfecto, LFS etc. are willing to give me a
straight answer. So again, I am asking for opinions from people with
experience in aquaria and engineering. Do I need to replace the
plastic frames because of the fine splits or just ignore them and fill
the tank? The frames aren't costly, but the labor is a pain, and I'm
finding it difficult to get the frames shipped to me as they are
oversized for UPS and most carriers (read expensive to ship).