The close-to-end result after one big botched attempt at this and some redesigning on the fly:
The rails are attached to 90deg brackets which sit on top of some diy bushings of sandwiched steel / rubber washers.
When it’s time to install the drawer I am going to drop bolts with fender and lock washers through the floor of the drawers, pre-attach the little spring loaded t-nuts that fit in the rails and then feed them into the long way of the rails. The cross beam also has two nuts loaded in already and the plan is to loosen the cross member a little to slide everything into position for two more bolts laterally. Probably overkill considering I only have 6 attachment points to the body, but oh well.
There are also some leveling feet underneath. Was playing with them, but they’re not really doing anything. I think the rails are mostly pressed into the layers of sound deadening / jute fluffy stuff / carpet.
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