The wires are about 10 inches too short. In normal wiring one would make a junction box and wire up extensions, but there is no place for a junction box inside the unit, of course. The original fan motor also used a flexible metal conduit, although the new fan wires appear to be overinsulated for outdoor use. I will have to use a dedicated ground if I eliminate the metal conduit, and one is on the new motor but I will have to extend this as well. How do I proceed?

I GREATLY APPRECIATE IT. A 'reputable' company wanted to charge me $500 bucks to replace this motor. I think not.

You Can Try Running New Wires From Your Contactor To The Motor And Use Wire Nuts. JUST MAKE SURE YOU TAPE THE CONNECTIONS AND WIRE TIE THEM OUT OF THE WAY OF THE FAN

Butt connectors are much slimmer, if you must use wire nuts stagger them so al are not in one spot.