Personally I have no idea. But in trying to see any ‘disassemble’ instructions, I came across a few photos - it would appear that there are electric connections, spring, etc., inside, that might be a ‘reassembly’ issue. Perhaps the screw is epoxied for a reason.
Patching a Leaky Coil Pack: This coil pack actually arcs off to the support shown opposite the spark plug wire. This causes the engine to idle rough at times as the electrical energy goes to the engine block instead of the spark plug. Time to fix this nuisance.