We were going to call the vet Monday to schedule that test. It is
Saturday night at 11:00 I catch Andy trying to pee on the carpet.
(another blockage) I know we should rush out to the emergency vet, but
I decided to wait until morning (it is now almost 1:00am) and see what
the night brings. He may well be dead, have I not done more than most?
am I evil?
When is the point when enough is enough?

The biggest problem I see with your post is that the cat is probably in extreme
discomfort from the blockage. No matter what you decide, it's wrong to let him
suffer for 8 or 9 hours when you there is an ER available to you.

Sherry