Anything that allows the electronic trigger to move, even slightly, will result in erratic ignition timing, and every degree of rotation at the distributor translates to two degrees at the crankshaft. I'd reccomend using a little rubber cement, or maybe some High-temperature RTV to minimize the wobble. You can correct any timing error by turning the distributor housing, but the trigger ring shouldn't have any movement relative to the cam lobes at all.
Jerry