Used model number to look up motor needed. Ordered from AppliancePartsPros online. Had the part in 2 days. Unplug, turn over, pop off cover on bottom. unplug and remove old motor. attach wiring and insert new motor. put cover back on, flip micro back over, plug in, done. Took maybe 10 minutes to do.
so... less than $20 + 10 minutes = not buying a new microwave (saved about $140.)