Quantity of seam sealer needed for mk1 fenders?

[area53 at validpath.com (Jeff Toomasson)]

Happy Friday, everyone!

I'm a couple days away from mounting my replacement fenders and I'm going to 
buy the 3M Body Panel/Seam Sealer to glue the fenders back on, but I was 
wondering how much I'll need. 

I don't want to buy a crap-load of it and then use like 1/8th of it...(unless 
you're trying to duplicate the stock application which makes the term "apply 
generously" look foolish... ;)

Thanks!

Jeff