XXL: 45″W × 40 1/2″L × 16″H [12] (one user measured: 40 1/4″ (Y-axis) Front to back (from outside of black bracket on each end) × 44 13/16″ (X-axis) Left to Right (from outside of black bracket on each end).[13]
Converting that:
114.3 cm W × 102.87 cm L × 40.64 cm H
and that page now reads:
XXL: 45″ (114.3 cm) W × 40 1/2″ (102.87 cm) L × 16″ (40.64 cm) H
Please look at the balance of the number on that page — some folks don’t include the electronics enclosure (hangs off the left side in the standard design) in the footprint since it doesn’t contact the table.
My suggestion would be to take one of the 3D models, change the rails to 40" long, adjust everything else to match, add some vertical height (XL and XXL endplates are taller than the SO3) and work from that.