That comp and timing sounds Ok...
I run 98 vortex also less likely to foul plugs.
Optimax ssems to have detergent additives which produce incomplete burning and fouls plugs, and you have to throw them away. The fouling is caused by carbon deposits inside the plugs which causes low resistance and the spark tracks inside the plug intead of across the electrodes and you cant clean them up again.
I run a 54/96 cam but I dont think that would make a difference.
Try a complete drain of the fuel and ensure its clean