Adapter S58-short to M68a – for all BDS Diamond Steeltrack®

I have a 2" Steeltrack Focuser and a 2" Clicklock Diagonal with Nosepiece. I want to direct-attach the diagonal to the focuser. I read in the manual that I can remove the nosepiece from the diagonal and the eyepiece clamp from the focuser. I did both successfully. Both I seem to be missing an adapter to mate the diagonal to the focuser. I think it is an S58 with Dovetail. Can you tell me whst I need? And instructions. Thanks!