i’m wanting to change my interior in my 97 to black. was wanting some insight on how to go about that…also would converting the interior to black myself (besides the seats) be a mistake??

 

I'm sure a parts car black interior exists. The seats are easy, but if we're talking headliner and carpets that will be a pretty serious effort.

I've personally never seen it done on a 400. It's a lot easier just to get a car that already has the interior color you like.

 

easiest is to find a car with black interior and swap it in. that is likely very difficult to find.
so next is to dye the material (leather, vinyl, cloth, etc). each material requires different products for proper adhesion. youtube has many tutorials on how (any many fails too)!