Simonis is a whole nother breed of cloth.
It HAS to be stretched tight as it will stretch quickly.
When you felt the rails they better have ripples in them or they will get so loose in a few months they will pucker....
I wrap the felt in my fingers as tight as I can and lean back as hard as I can and get a few staples in it to hold it.
Technically, you could lay the felt on the table and trim it to where you could see over 1" of slate on the table, and they is just about right for how much you are going to stretch it.
Just do it evenly and try to make sure all of the fiber marks in the felt don't get wavy from being stretched unevely...
I have Championship Tour Edition on my 9' table and I stretched it so tight I was scared it was going to rip don the center when I was pulling it! But, it is the fastest best rolling table I have ever played on...
My CTE edition is about 10% quicker than Simonis. My buddy has Simonis 760 on his GCIII and the first time he played on my table I asked him to lag. His lag came all the way down and went half the way back. On his table it would have froozen...