vinyl top bow support

I bet it was just brushed on contact cement (like Weldwood from Lowes). Brush it in both surfaces and allow to dry to a tacky finish and then stick pieces together.

Yup, contact cement is awesome stuff. Great for top material. I use it to stick valve cover gaskets to the valve covers too.

Good Lord, there's half a zillion 'contact cements' on the market...each one claiming to be the greatest stuff since Saran Wrap!

Independent testimonials aren't much help since they're inconsistent and often contradictory. Consumer Reports tantalizes that their testing reveals some are fantastic while others suck..."press the subscribe $$ button now to access an entire year's worth of reports on every consumer product in existence"

Life is always about money,... isn't it 

I've used DAP Weldwood.  3M makes adhesives too - even an easy to use spray.  You want the solvent based vs the water based.

Yup, DAP Weldwood, available in the paint section of any home center/hardware store. I buy the small one, it has a decent shelf life when opened, but not more than a few years.