I have two of these that need a good home. The layout is intended for a 1590A using two pcb mount 16mm and one 9mm pots but of course you can off board wire the pots and put it in any size enclosure you like. These are verified as I've built a few with these boards. $10 ea plus postage.
https://www.dropbox.com/s/7stp4yebopnrgvf/pcbs.JPG?dl=0
Thanks!