I have a 14" round drop base aircleaner. This is stamped aluminum with smooth flowing curves into the the carb. I can't check it as I'm traveling this week but I would guess that the top of the element is the same height or slightly higher than the aircleaner mounting surface of the carb when using a 3" tall element. I really like this product.
I bought it from CV Products in NC. About $50 w/o element.
http://www.cvproducts.com/cv/
Their website is a pain to use, I'd just call to get more info. I think that it is listed under the CV Products collection but didn't wade through all of the pages looking for it.
Jim