Optimal results require 1.5mm reduction for occlusal surfaces and 1.2 circumferentially. The margin can be either 90 degree shoulder or a 120 degree chamfer. Marginal fits of less than 30 microns are routinely achieved with either preparation method.
Opposing model is needed if bite is close.
Expansion cements can not be used, but all other cements are fine. Recommended is Panavia 21 . You tell us. We generally will assume the average 10 working days from the date we receive the case to when it arrives back at your office. However, all you need to do is call us or request a rush case date and we will, by all means possible, try to meet your schedule.