Remove the handle. Use your deepwell 3/4 to 1 inch mechanic sockets to remove the valve or buy or rent the socket from your local ACE hardware store. You can sometime also remove the valve extension covers and then remove the valve with a box end wrench.
I usually fit spout 6-8 inches above tub.
Mixing valve usually for tempering domestic hot water.
mixing valve in a faucet: ok I will assume you are refering to a shower valve, that is the only faucet w/a mixing valve: shut off the hot and cold water. cut out valve or unsweat it. clean and flux new valve, pipe and fittings(if used) sweat in new valve
Once the old tub gets into the drain it is impossible to remove.........
With a tub strainer dumbell wrench.
There should be a drain valve where you can hook up a hose and then open the valve to drain.
The optimum way is to remove (unscrew with a seat wrench) the seat and replace it. A seat cutter tool may be used to refinish the seat in place.
The purpose of a thermostatic mixing valve is to mix hot water with cold water. This is what keeps the constant temperature in both bath and shower water.
A tub faucet acts as a shower and can be used to bath in the bath tub. It is a pressure valve which makes the flow of water through it constant and gives a nice shower.
NO - you would have to change valve out
By disconnecting the tub shoe from the waste tee and removing tles around the tub
you need to compress the spring with a valve spring compressor tool, and then remove the valve keepers, and retainer.