[356RS]

BSNMOE, Removing spacers will not speed up the expansion movement and will also add more free play to the shaft and that will just add more time for the disc's to expand and take up the space before the shaft starts to move. Don't worry about the shaft having to much pressure moving froward. The lever inside the pump has a very strong stop mechanism. I would think the best method for fast warm up is to make sure your hose is the correct OEM type and has no leaks and provides good flow through the thermostat.
Matt, I must have missed that concave to convex disc arrangement information. Can't see how that would speed things up. I have a NOS thermostat and can try that method on the bench and see what happens.