Convertible top frame

I'm having problems adjusting my windows to fit the top. When rear and top of the door glass appear to fit correctly the front bow sits to far back on the windshield frame. This car was a basket case when a got it and the top was not installed but I believe the top frame is the one that came with the car. My shop manual implies that the front bow can be adjusted fore and aft to correct this problem but offers no insight that I can find as to where this adjustment is made. Also the front bow has been welded to the frame I don't think this is right. If the front bow is supposed to be adjustable then I'll grind out the sloppy welding job and go from there but I'd like to know if the front bow is really adjustable. Also does any one have any tricks, tips, and/or techniques for adjusting for a good fit with the door glass.
Thanks

Hi Dave,

Check out the replies and the web-sites referenced in these two threads ('Replacing Soft Top?' and 'Convertible Top Replacement'). Might be of some help.