[67 Convertible]

I believe that before they proceed with any work that the customer will be charged for, they have to give you a written estimate that you sign off on before any work starts.

Sounds like they told you it was the fuel injectors and it would be covered under warranty. Then they went ahead and did the work, after the work was done, have now decided that you should pay?
Don't think it works like that......

Was the FI replaced with the new motor?

Why do you keep going back to the same dealer who replaced a cooked motor for low oil, and gives you back the car with the new motor 2 qts. of oil low and the tunnel brace falling off?
I would have never stepped foot in that service dept. again. Gotta be more to this story.............................