The stock armboard is approx 1" thick. I went to the hardware and bought nylon standoffs 1/2 and 1/4" long. These are 3/8" size. By using standoffs between the bottom of the armboard and the base, you can reduce the armboard thickness to 1/4 or 1/2". I used oak. Seems to be a better coupling of the armboard.
Regards,