'74 Lightning Energizer ignition -- help with rotor and cap???

[Grumpy Bear]

See pic. I'm guessing the rotor must come off before I can remove the rest of the cap? Either way, obviously, both must come off, and it's stuck on pretty tight. I have a wire (white or blue, not sure which) that is shorting and need to get to them underneath. The plastic is old, combined with all the heat over the years, is fairly brittle and I don't want to crack or chip it up horribly trying to pry it.

Any ideas how this thing is supposed to come off??

Thank you!
Kevin

 

[Faztbullet]

Need to get the special tool...find a old Merc dealer and see if they have one