Alphason HR-100S Arm

Recently acquired an Alphason HR-100 arm and like other users am curious about adjusting cueing arm height..can't quite figure out the size or type of tool to do so ..and am VERY reluctant to continue probing around in there ..any help would be appreciated 

Thanks all... I've seemed to have heard in circles it's a 0.35  Fleib could you explain "goes in on an angle"?

Hello

so I am at my wits end with the sizing of the hex wrench for the HR-100. I have under the recommendation of John at Audio Orgami ordered a full hex set that has royal as well as metric sizes to no avail,either it's already stripped and can't be removed or it is some other fitting. John did confirm that it's one of the "earlier" arms with the glued in leads. Not sure if this helps please advise,even how I can remove the screw and use a similar sized one with a comparable thread.

thanks