I had an older Grizzly 14" saw once, long ago, and I can tell you, that if you're trying to make a re-saw out of it with that riser, and actually thinking it will have usable capacity that way, then you're shoveling something really nasty against the tide.
I would get rid of the riser to start with, then align it as best you can with a decent blade, and live with it's standard capacity.
For re-sawing, bite the bullet, and buy one of these blades for the saw, in 1/2" size, 3-4 TPI :
https://timberwolfblades.com/index.php.
Don't kid yourself that a wider blade is going to be better - If everything is optimal with that saw, then 1/2" is really the limit, IMHO.
If you want to resaw, then fab up a
single point fence (Look it up) - A straight fence won't work well for that, unless every planet in the solar system is aligned, and/or you have, or buy, a much better saw.