You are on the right track... We do this off and on to shape traffic (move where the ring is blocking) or replace hardware. We always leave a port disabled till new switch is up and EAPS has seen all of the devices in the ring. Once you have double checked the new switch config and made sure you have the configs right and it sees the new master you can enable or plug in the second interface in the ring to complete the ring. Biggest mistake that happens is forgetting to enable EAPS globaly on the new switch..
Show EAPS (eaps-name) will confirm it is running, setup as transit, see's master, and has same number of protected vlans/vmans as master.