Same a it ever was
As a Cozy builder and pilot, you'll find that 99% of the engines for the pushers are the same as tractor configuration and rotate left. We do it simply based on parts availability, commonality, etc.
Baffles will be different, as most EZs cool with updraft cooling. If it is fuel injected you'll find most of the spiders on pushers located underneath in the "cooler" air, whereas you'll want it up top.