I've bought the MM solid shaft, it didn't do much for me in this situation.
I checked all 3 of the pinch bolts (2 interior, 1 exterior) and they were all tight, no play there, I can maybe hear some play in the steering column between the shaft and the wheel, so I ordered a used one off of ebay to tinker with.
I removed the airbag and checked the wheel itself for play, removed the bolt and retightened, and even with the bolt out, there was 0 play there (FR500 wheel, was a lot tighter on the column shaft than the original 95 GT wheel).
Under the dash, I could put a 1/2" wrench on the slender portion of the slip-shaft of the MM steering shaft to hold it still. Then I could detect little to no play, not enough to manifest itself when driving (so even if there is play in the column, its not enough to be noticed when driving). So much for that.
So its the steering rack, I can't decide to try the pinion adjustment AGR mentioned, or just purchase a new agr rack from summit and send mine back to AGR. If I could find a 03-04 cobra rack, I'd get it, but OEM racks are fetching $500 from the dealers and there's no guarantee on which rack you actually get.