TP, personally, I wouldn't use silicone for anything...over the years, I have seen it fail virtually everywhere I have used it...way back when, we started using the auto glass sealant(also know as EBS...evil black stuff) due to the recommendations from the Camp-Inn folks...since then, we have experimented with a number of different sealant/adhesives and the EBS has been among the best, if not cheapest...it is a urethane based product and something like SikaFlex 221(available thru Austin Hardware and other marine outlets...it is also urethane based) will work just a good if not better and is cheaper...butyl tape also works well(not butyl rubber caulk)
madjack
p.s. a tip about the EBS type of sealant...DO NOT try to clean the "squish" out, before it has set...allow it to set up and you can peel it off..............MJ
p.s.s. another tip...put a dab, of whatever you use, in all screw holes, before putting the screw in(we predrill almost everything).............MJ
http://www.austinhardware.com/dept.asp?dept%5Fid=452
...I have come to believe that, conflict resolution, through violence, is never acceptable.....................mj