I cant help but to go along with the friendly advice given on your current frame situation,.... and will probably end up with my foot in my mouth,...BUT, if a nice narrow frame pops up I would buy it to replace what you have. You can save your self a lot of work . But then again, you could have a Ace up your sleeve and I'll fold!
Here is my frame to my model 72 in it's present state. Waiting for spring to begin my build:
Good luck, please keep us posted in matter of your frame!