Thermostat and Thermostat housing and coupling

[Corvette95]

I removed my thermostat housing since I had the room, I went through the solutions, seems to be a lot of issues about which thermostat will work and which won't. I ordered a 180 degree "fail safe" thermostat from RockAuto and gasket/seal (pic below minus seal) . It looks correct as to what was posted online, but the thread was from 2013. I don't have the new thermostat in my hands yet, it is due to arrive Monday. What is so different about the LT5 thermostat? I also want to get a new plastic retainer for the housing (see pics below), and maybe a new coupler if available. There is only one bolt holding the thermostat housing on, what precautions should I take in removing the old thermostat and installing a new one? It looks pretty simple with the housing off, but have read many threads saying how difficult it is to get the housing back on with the seal in place. I know to when it comes to it, I need to get the air out, there are several different methods, I was going to try to reverse bleed it with air blowing in from the driver side and using vacuum at the tank....suggestions? See pics below...I am planning on soda blasting the housing before I put it back on. (1990)