Operator arm hole diameter

A landlord from Denver says:

date: 09-02-09

The arm extensions on my old windows have a pin that slides into a 5/16" hole at the end of the operator arm. Can the arm extension on this item be removed and if so, what is the diameter of the hole at the end of the arm? (the operator that comes in the kit (39-165) seems to be just what I need, but I don't want to pay for all the extra hardware I will not use) Thanks.

date: 09-08-09

If you were to remove the forearm, you would have a 5/16" hole in the main arm. However, you might want to keep the forearm on and try it that way first before you through the trouble of extra work.