I am working on some #4 brushed stainless steel inner scuff plates for the 280Z. They are modeled after the the later 280Z plates but I also put them in a 76 that had the early 280Z scuff plates and they fit great. In the early 280Z's you may need to drill a few 1/8" holes for mounting is all. I will also offer the option to powder coat them black (they will still be the same stainless steel under the powder coat). I can also look at making them for the 240Z but I know that those are still available to purchase... If there is enough interest for the 240's to have stainless steel scuff plates I can do that too.
I should have these up at skillard.com to pre-order this week and should have them ready to ship early January. The price point isn't finalized yet but it's looking like $80 for a set of 2 with stainless mounting screws. Add $10 for powder coating.