Apologies for the delay, Dakar is up so... quite busy following the race
. Other than that a hectic week at work and everywhere else basically.
Have a look below.
Let's discuss the above design a little bit.
The above will fit a Touratech roadbook without leaving any space on top and bottom. I see that you have some zip ties beneath your roadbook but that is a no go in the above design. If you want I can add the button extention below the Touratech so you will in general have something like the top plate shown at the video at the end.
The IMO will go on the right. I changed the bend at the end of the tower plate to -90 deg, so now it is looking upwards, it provides some protection to the IMO. On the left, the space is open, as requested, do some measurements in order to make something that makes sense. On the top you have some space for Nav equipment. Let me know dimensions so I can edit that top space for you. If it is too big it just does not look right.
The four parts, shown next to the plate, fit below Touratech and they are used to ''grab'' the thing that you circled in red in a previous post. Bear in mind that I used bolts with a square shoulder so I dont have to take the touratech rb out when doing adjustments. You can find these in any bolt shop.
The other thing is that the above may need a stiffener at the bottom. (look at the video, on the rear side where the pivot/adjustment bolt is bolted) This should be welded, and it really depends on the design if you want to go for a middle one or two stffeners one at each side. Unfortunately, I was not being able to test my tower extensively, it was a solid rock for 100 racing kilometers and you could tow the bike from it.
So, all in all I think you will be ok with just one stiffener in the middle.