79 Volare
Had a 77 Roadrunner (Volare) that did the same crap until I put a 650 Holley on it. I was told that the float in the carb was changed from a center pivot to a side pivot for emissions and it was more prone to sticking and causing the engine to flood when I took it back to the dealer to find out why it ran like crap.
To answer your questions:
180 degree thermostat. Don't need anything higher since you don't have fuel infection.
Use gaskets on the intake, RTV on the ends of the manifold. Always had good results with Permatex HiTack on the gaskets, no leaks, no mess. There may be locating pins in the valley rails at the ends of the intake manifold. Make sure you get them out or the intake will not seat.
Shouldn't have any problems with the throttle cable you have. Mine worked on an Edelbrock Torker with a 650 Holley.
Hope this helps.