Up here in Canada you can buy a product by Permatex called Flowable Silicone
Windshield glass Sealant. Comes in a blue blister pack and as the name
suggests, is specifically for leaky seals. I used it on my baywindow about 2
yrs ago, with complete success on the windshield passenger side corner. It
is a very "seeking" product; it crawls down under the seal and you think it
won't flow when you first put it on, but you'd be wrong. I came out a few
hours later and couldn't find where I'd applied it. It had crawled down
under the lip of the seal as intended. I think it's great stuff, and will
probably buy you time. My time has been 2 years; darn, I gotta get on that
body resto. :-)
Courtney

========I'm thankful to all those who said "no". Because of them I did it
myself.========