Rockport questions

I have a question for the Rockport experts out there. I got a Capella secondhand, without a manual (they don't seem to be available) and the gasket needed to to be replaced. The replacement gasket is folded. Does the fold go over the outside rim of the platter, or does it get folded under so that the gasket rests on top of the outer rim? I tried it the first way, and the vacuum doesn't seem to hold a seal that way. Also, the pictures on the web seem to show the gasket folded under and overhanging the outer rim (the pictures are a little hard to decipher). Your help would be appreciated.
On related topics, does anyone know the correct pressure for the vacuum and for the pump? The arm is the 6000 model.