XS650 chains mostly have a clip type master link, look for it.
My niche chain also came with a clip type master link.
My niche chain also came with a clip type master link.
What you really need to try is learning how to properly route cables, lol. You can't have sharp bends and kinks or the cables won't operate smoothly. Your clutch lever is going to be a bear to pull with the cable like that. Properly rerouting cables with really low bars is difficult. Personally, I think they're more trouble than they're worth.
Bike looks good!
I'd be inclined to find a Standard seat or at least a Standard seat pan to swap/fab that Special seat foam and cover over to. My linear eye jams to a screeching halt where the side cover and seat don't match, the dreaded gapsitis.