EH AC cable 'grommet removal'

[analog kid]

I surely hate to have to post to get some help with this but I can't find anything about it anywhere so far.  I have repaired quite a few AC powered EH fx cords , replaced with new one or removed and installed DC jack for powering a regulator direct to circuit.  HOWEVER they have always been missing the original grommet that holds the AC cable from cutting on the case!
I am trying to shorten and rewire to the power kill switch , the power cable on an old polyphase I fixed, due to some bare wire / breakage near the grommet... Thing is I can't for the life of me figure out how this grommet is meant to be removed/replaced!?  I mean I can push it outward a bit pushing from the inside but then it stops. and there is a little 'tabbed' section that looks like it could maybe be meant for pressing in on or pushing out w/ a screwdriver or such but I can't figure it.   I mean I assume there made to be removed and re-inserted(??)
I  assumed there'd be alot of dealings with this around here and a few posts but i can't find them.
  anyone with experience with these , I appreciate it!

[Processaurus]

get some pliers and on the inside end of the grommet, squeeze the movable part (that closes the slot that the cord goes in so you can get the grommet on the cord) hard and push it out hard.  Don't worry about damaging the AC cord from the extra squeezing, its tough.

[analog kid]

Ok thanks.  And what an angle that thing is in there at escp. sitting right over that spdt slide switch!  I got it , this thing was a real rusted piece and I believe that had taken affect on the grommet as well.  but it is supposed to come apart as two pieces after removed correct? slide the fresh ac leads in there and press back together And THEN push it back into the hole?
  also since you may be able to be of help with this.  any tips on how to wire the spdt for power on/off? the way it was it was just  jumpering the ac cable and transformer 110v side leads together on either outer lug!! obviously NOT going to get a "switchable" power that way ... but that's how it was and didn't look like it had been touched in decades.
  How is that slide switch best to be wired for on/off in these units?  I am sure I can wire it up to kill the power real easy but I'd like to know how it's supposed to be for sure.
thanks man!!

[Processaurus]

No problem, the first time i took one of those apart I was suprised how merciless you had to be. 

Yes, it goes in the same way it came out.

for the power, use the switch as a spst, and just interupt the mains voltage to the transformer, doesn't matter which side as long as the circuit is broken by the switch somewhere.  Heat shrink it up good, it can hurt someone bad if theres any way the 110 can get on the metal chassis somehow down the road.

The pro safe way to make it 3 prong but not have groundloops is to ground the chassis to the 3rd prong, but replace the jacks with all insulated jacks, so the circuit & instrument ground goes out through the instrument cord to the amp rather than the power cord, but the chassis is always grounded soley through the third prong.