Dash panel covering
Not sure if the 300D uses the same dash as my 380SE, but I've seen both dash covers (generic Dashmat types) and vacuformed plastic overlays for my model. I'd check evil-bay, and send the seller an email stating your year and model and see what they have in stock.
I've never used the plastic overlay covers, but a couple of big problems with the dash mats is that to secure them, they usually give you little velcro stickies. Looks pretty lousy on the dash, but if your's is already gone, I don't see how it would matter much.
The local flea market has a guy that makes dash covers, and I suspect that I could get them to sew some of the rubber no-slide backing that you put in cabinets to the back of the cover, and then it wouldn't go *anywhere* or require me to put little glue backed stickies on my dash. Has anybody ever tried that idea?
Glenn in Tucson
84 380 SE