Simple Project ?

I was watching a DVD about tablesaw use and decided to make a zero clearance insert for my 6 month old Delta CS. Seemed simple enough. Used my planer to get the thickness and the bandsaw and belt sander to shape it. I did all my test fitting with the blade out because I was going to use a new one. I intended to clamp across the new insert and raise the running blade thru it as in the video,but.. The blade, when all the way down, is less than 1/8" below the cast iron surface(yes its a 10" blade). I thought about tilting the insert into the running blade like tilting a fixed base router into a work piece when you have no plunge. But that seemed way to scary. I solved it by switching to an 8" blade, then stepped up to the 10".

As a side note- When I assembled the saw I wanted to do it right this time and install the guard. As per instructions I installed the guard, then the blade with the arbor all the up. When I stepped back and looked. The guard was sitting at an angle, The pivot pin thru the guard was sitting on the back of a tooth. When I rotated the blade it fell to rest right between 2 teeth, So off it went.

Do I have a problem, or is this the way there made these days? Maybe I just have more depth of cut than most . The saw in the video was also a Delta CS but a few years older.