If you wanna try the easy way to basically hide the scratches you could try a color restoring car wax like "color magic" or similar brands that are tinted the color you want and hide imperfections.

The EL panel, there might be a way to do that with etching an acrylic or perspex panel and edge lighting it with LED. ... if you can't find a bad connection, I have heard ELs don't last all that long.

SETBLASTER wrote on 2023-10-29, 02:42:

This year, i was able to buy 2 PC cases that are very iconic for retro PCs. […]
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This year, i was able to buy 2 PC cases that are very iconic for retro PCs.

Some months ago i was able to buy :

A) Thermaltake Xaser II : black case, everything included, even with the orange fans. With some flaws tho, the Molex connectors broken, or some fan cables not making good contact and needed to twist those for the fans to start running, so i will be replacing the fan cables and connectors and even doing Expandable Braided Sleeving for the fan cables. One strange thing about this case is that in the front , its supposed to have some red anodized aluminum plate, but this one its not red, its silver.

B) Thermaltake Xaser III : black case, eveything included also with the orange fans.

Both of the cases weight a ton. It is kind of crazy to understand how in 2003 they shipped these from taiwan being so heavy.

The problem with both cases is that both of them have been treated really bad on the top. The black metal top part of the case is all scratched, i don´t know that they used to put on top of the pc case to scratch it like that.

But i am not sure what kind of black paint they used, i am very sure its not gloss black paint, but not sure if it is Satin or Matte, or if there are different types or tones or black in the market.

Another thing that seems not working is some weird EL (electro luminescent) panel on the Xaser III, that is supposed to have the "thermaltake" word in blue when you activate it. I have been looking for such panels on the web but none matches the dimensions of what the original thermaltake used. So i am still thinking how to make an alternative to it. seems like those EL panels after some years stop working or they break the connections and burn.

Some people hate the design of these, but i find them very attractive. Considering that for the era there was not much in the market to choose if you liked to mod. Much of the pc cases from that era were still beige and boring, without a side window too

I posted a couple of links for EL replacements (including 6 x 2 inch ones) in this thread - Thermaltake Xaser electroluminescent (EL) light panel broke, looking for replacement. - though not sure if any would be suitable size-wise

SETBLASTER wrote on 2023-10-29, 02:42:

...
But i am not sure what kind of black paint they used, i am very sure its not gloss black paint, but not sure if it is Satin or Matte, or if there are different types or tones or black in the market...

Normally PC cases are powder coated. Its super difficult to match the colour and finish with regular paint.
If you really need to paint things and a touch up is not enough, paint the whole thing so you dont have to live with different shades of black and finishes.

BTW:
If i remember right, you can cut el panels to size with scissors.