Replacing Happ Coin Reject Button Insert Labels

[quarterback]

I have a CoinControls over/under door on my upright cab.  The coin rejects come apart and allow you to easily change out the reject-button labels.

I just got a Happ over/under coin door with the Happ coin-rejects which are, clearly, different.   They seem to have a 'slot' to slide the reject-button inserts in and out.   I've poked at it with a jeweler's screwdriver, but can't get the inserts out and I'm afraid I might eff-them up while I'm poking around in there. 

Is there an easier way or a trick to this?
Thanks
qb

[quarterback]

Just in case anybody thought this was an April Fool's joke, I thought I'd give it a bump.

Anybody?....

[Franco]

If I remember correctly, when I changed mine i used a very thin metal ruler to push the insert out of the slot. I only managed to get the ruler partly into the slot but this pushed the insert enought to then be able to pull it out from the other side. If you have a feeler gauge set it would be even easier.