Hey Dave, I made mine from 16 ga ( .0598", 1.518mm) 304 Stainless steel. If you go with Aluminum, I would go with 8ga Al .1285". Bear in mind you might get some interference in the bottom corners near the hinge as there is a sheet metal feature on the bed that is present. I've attached my 2D drawing for reference, drawing is not complete as I pull data for mfg from the 3D model. If you are interested in a stainless one, I can have my shop make one and drop ship it to you. You would just need M6 screws and 30 rivnuts to complete the install. Price is $160 plus shipping.
Cheers, James
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