ReSTored and all, my apologies for the delay in getting this posted... I ran out of steam after going to 4 stores to get the groceries and ended up with a beer in one hand and a book in the other.
Here are the promised pics of the adapter I built. It's built out of 3/4" plywood, 30" wide by 92" long. The underlying frame is made of 2x4's assembled with 6" structural screws. The top is screwed down with 3" construction screws. The adapter is secured to the Quickjacks with a piece of 3/4" steel tube and a couple of R clips. The bikes are secured with steel rings screwed through the plywood into the 2x4s. The steel tubes, rings and the screws, structural and construction, I happened to have on hand. I purchased the plywood and 2x4s for the project, which is where the $50ish dollars comes from.
I mounted a chock I happened to have on hand but will use a steel place as a stopper at the front if one of the bikes is going on the centre stand.
For storage, the adapter and the Quickjacks lean up against the wall in Garage Mahal. It is quite heavy for me and my arthritic hands so normally I'll have some help me get it into position for use. The Quickjacks fit neatly between the 2x4s.
I have had my ST on it as well as an 83 V45 Sabre, shown in the pictures.