Some Nice progress there. Have you considered buing grp sandwich panels and building a box from that yourself?
Should be just as DIY friendly as a metal based construction?
Nice job restoring the dashboard, looks very clean!
Some great progress, great to see thing coming on nicely. I had exactly the same problem with the new window sliders, had to cut them as well. Seem Mrs Benz supplies a generic part that fits a few different vehicles.