I know this, I've done it a few times, I have a Midway cab that I occasionally swap out a 6 button KI2 control panel with a MK4 one, it's a very simple removal, permitting it isn't uber "virgin", my MK4 one I have to like use some finesse to get in and out.
it's as simple as removing 4 7/16" bolts, 3 wiring connectors (one for player 1, one for player 2, one for player 3 aka: the kick harness) and undoing a nut for the ground strap.
fear not though, I've fit these through small doorways before without taking the CP off. unless it's a very narrow door like a bathroom door size.
reinstallation of the control panel is as easy as reversing my steps outlined, but be sure that you get the CP mounted as flush on the bottom as you can get it, you don't want any noticeable gaps. your latches will latch tighter too.
good luck with the purchase, I wish I had a dedicated MK1 cab :/