HOTAS case attachment method:
I will purchase 2 x 6mm (but possible 5/4mm) plates for the top of the supporting poles. The poles are to be made from hardwood. I used this on my monitor mount for my rig and it's very sturdy:
The plan is to drill 2 holes into the bottom of each case. I will pass a bolt through each of these and use a washer also, These will be epoxy'd in place to prevent any movement.
I will drill a hole into each of the supporting poles which will be embedded into the pods located at the side of each seat. Each hole will have a threaded insert screwed into place.
The aluminium plate will be attached to each pair of poles using coutersunk bolts.
Each plate will have 2 channels cut into it.
The bolts extending from the underside of each of the cases will pass through the channels and will be bolted in place from the underside.
The channels will allow a degree of fore and aft movement.
This is the design:
The channels or counter sunk bolts may be off-centre depending on what it is like getting into and out of the seat - I don't want to inadvertently catch them getting in and out.
It may be possible to use only one channel between the poles and pass both attaching bolts through it. The basic principles remain the same.