OK, it has been awhile, but I drove the the car over a hundred miles yesterday and all is well...better than well, actually because while I had the car down I sent the injectors off to be tuned up.
What I learned about changing belts on a quad cam Subaru, even though I had done this before:
1. Don't pay attention to the paint marks on the sprockets.
2. Before starting the job roll the engine over so that the two (2) scribe marks on each sprocket are pointed to each other, and the crank sprocket has its key way at the 6 o'clock position. There should be a mark on this sprocket at the top that aligns with a mark on the block at this time.
3. Now you can remove the idler rollers. The cams on the right side (passenger side in the USA) will just sit there as they are unloaded. The cams on the other side will more than likely spin suddenly, as they are loaded.
4. I recommend replacing all of the idler rollers if the engine has any where near 100,000 miles on it. Mine has 95,000 miles. The manual says replace them if you can hear them when you spin them. The kit I ordered came with the tensioner, even though the description said it didn't.
5. If your engine is a turbo with a 5 speed, the smallest roller included in after market roller kits will be wrong. Rockauto.com gave me a credit for $40, the correct roller from the dealer was $83 and I had to drive a hundred miles to get it.
6. After you get the belt in, pay attention to the scribe marks on the cam sprockets! The double marks must be pointed directly at each other. The right side marks are difficult to see without a mirror if the engine is in the car.
It is easy to be off a tooth on the right side.
7. When everything looks well, pull the pin on the tensioner, and just for ducks, check the torque on all of the rollers you replaced.
8. I recommend cranking the engine two revolutions by hand, this makes every cam rotate once. By this time the belt should be running straight on all of the pulleys and sprockets.
9. Put the rest of the engine together (preferably with a manual) and the
engine should fire up in the normal manner.
The mistake I made that caused me to start this thread was that I was concentrating on the paint marks on the sprockets, not the scribe marks. I had installed the belt with the left side intake cam 180° off. I was fortunate that I didn't break anything.
Thanks for holding my hand while I worked through my problem. I did take pictures, but I can't find my camera (go figure).