Carefully drill a 1/4" Hole in the center of each hub. Cut two 4 inch sections of 1.5"X1.5" aluminum angle and drill a 1/4" hole in the center of one side of each. Attach these to the hubs using 1/4X20 bolts about 1.5" long. Use some sort of lock nut on the inside of the hub. A socket wrench with an extension reaches inside very nicely so you can tighten it securely. I used some 1/4" thick aluminum plate cut to a square that fits between the two angle plates for the telescope mounting part. Drill a couple of 1/4" holes for use in bolting the PST to the plate. I use a hand knob with a 1/4X20 thread to attach the PST.