I hate to sound thick - but where's the 'bottom edge' of the top tube? Do you mean below where the weld point is?
My frame description knowledge isn't the best. I need to take a language course in how to describe parts of my bike....
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Recess (aka John)
www.recess.co.uk
"I feel sorry for people who don't drink. When they wake up in the morning, that's as good as they're going to feel all day."
Frank Sinatra