Happ coin mech screw size

[khargy]

I'm just about finished my first arcade (yay!)... one minor thing I have left is to switch out of standard yellow reject buttons to blue and red. I have a Happ 2-player coin door (#40-0008-00). As far as I can tell I need to remove the coin mech (or at least the top two screws) to remove the reject button housing... for the two screws on the center of the housing I used a 3/16th nut driver w/ no problem, but for the nut screws on the right the 3/16th is too big... and I can't for the life of me figure out what size it is... Anybody know what size those screws are?

[Applekid]

I personally used a 3/16 long socket for all of them. It didn't fit quite perfectly but it was the smallest I could find that was still deep enough to reach that close by the reject cups.

Out of the 7 per coin chute x 4 chutes (28 screws), I had one screw (just one) that simply wouldn't budge. I brought out the Dremmel and cut a slot in the head but even with a screwdriver it was pretty tough. I was considering replacing them with standard screws but I don't think I'd be doing that again to that coin door anytime soon. Thank goodness. 

[MonMotha]

Tried metric 4mm?  Most of Happ's stuff is made in Europe or Asia and is designed in metric.

[khargy]

Ok, I got it... they all are 3/16th it just so happened that the 2nd screw I tried was over tighten in such a way that it was actually recessed a bit... once I got the other ones off I was able to muscle that one off as well!