Coolant temp sensor and exhaust manifold gasket interference

[tucsonjwt]

I plan to replace the temp sensor on my 83 C20 454 but I have some interference from the exhaust manifold gasket (on the driver's side.) This is a
Goodwrench remanufactured engine, so I guess whatever company did the rebuild for GM was a little sloppy with the gasket install. Before I start hacking away at that gasket, does anybody have any advice on the best way to cut away the part of the gasket that is in the way of the sensor removal? I don't want to create a bigger problem for myself.

Also, do I need to drain out some coolant prior to the sensor removal?

I have a new connector with lead wire on order to replace the damaged one in the pic.