Excellent info, Multiflyer. Thanks!

I found out today why the right engine quit twice. The engine would run fine when it was the only engine running. But with both engines running at full throttle, vibration induced bubbles in the fuel line going to the right engine. A buddy and I fixed the problem by removing a bit of the padding from around the right fuel tank, making sure the tank was secure in the nacelle but not wedged in too tight.

I learned a great lesson today about some of the problems that are unique to twins.