What is the best way to set thetime on an svo? What is the best setting, 10 degrees or 12?

The best way is to loosen the distributor a bit and have a timing light handy. Then with the spout disconnected rotate the distributor and using the gun look for the white line on the front of the engine and set it to wherever you like.

10* timing is stock. I run about 12* for a little more low end grunt. More timing equals less boost you should run, and vice versa.