how to remove/tighten the ignition bezel in the dash

[heavy71chevy]

I have a 1971 c10 that ive been working on for awhile now and i pulled everything off the dash like the cluster and radion and heater controls so i can paint everthing from green to orange and i was wondering how i remove the igniton from the dash becaujse i dont want to get orange paint all over the key hole and chrome trim ring thing ..i got it alil bit loose by twisting it around but now if you try to start it you have to hold the back peice because it just spins the whole assembly in the dash..so my question is how do i remove the assembly and how do i tighten it back down once its completly out ..thanks ahead of time,
Heavy71Chevy