If your TD124 does not have a lid or you have the clearance to accommodate this custom version it may be a better option. Due to the overhang the armboard requires a 10mm clearance at the side. Your armboard is very good indeed - I have used most of the various boards available for the TD124, including the original acrylic 3012 board, and yours is by far the best sounding - well done!?.
eBay