Marlin is a machinist who arguably has unsurpassed knowledge on our Cleveland thermostats and the block off plate.
he is correct that neither of the thermostats pictured is designed for a Cleveland engine. Neither of them appear to have the hat that is designed to properly index with the block off plate opening.
as Forest pointed out earlier, the part number does not reference to a Cleveland engine.
you are not the first to go down this road but until you install a thermostat with a hat you have not fixed your thermostat problem
Go online and order one from Tim Meyer and all will be good.
Larry