LT1 is misfiring bad!
It could be the gas - I got 10 gallons of 93 rated crap at a BP in SC - it ran so bad I had to put 4 bottles of dry gas in it, then only rev it up to 3k - any more than that and it would break up really bad!
When I had room in the tank, I added 8 gallons of 107 Turbo Blue unleaded - Problem Solved!
(Oh, it could be a clogged fuel filter issue as well.)
However, if the driveability issue cannot be correlated to a recent fill-up, then your most likely issues are: An Opti, and Opti-to-Engine Harness 4-pin extension harness, an ICM, your coil, or a wiring harness (Open / Short to Ground / etc...) issue.
Check the 4 pin at the top of your Opti first - you might get lucky - and that may be your only issue.
Good luck!

