Wolftooth 30t ring with Zee mech and 11-36 XT cassette here.
My bike has ISCG05 tabs and also has a direct mount front mech plate. I use the E13 XCX direct mount top guide that easily goes down to 30t. In fact it would cover the chain ring better were it not for the chainring spider not being so prominent and the guide having to clear it (XT M775 cranks) I dare say with a direct mount chainring like the new RaceFace offerings you could run the guide with a 28t also.
Never dropped a chain on a ride using this set up for over a year, I race the local downhill series on the same bike and fit a DMR lower guide for that extra bit of security but it’s for peace of mind more than anything else.
Hope that helps