Going to post a few pictures in the next few days . Coming along nicely

Parts for alternator swap are here THANKS DAVE ! and mr220v !
Just have a question on the MR2 version the bracket that holds the engine hook to the block is replaced with a bracket that holds the alternator on the Celica version. Now both parts have a hollow piece
which looks like that there is a gasket. Looking at the block it looks hollow also so that the parts block it.
Question is there a gasket there. EPC shows one i think but its only available on the whole gasket overhaul kit...............
Can i reuse the one i have if there is one ?
Can i just unbolt it and quickly swap without coolant pissing out ? Its pretty high on the block. Should i pinch the water hoses to minimise the loss ?