If you go the television route, and want the arcade experience, get a CRT and one with RGB inputs.
CPS3 outputs RGB as do all the super guns I have seen, stay away from modern wide screen TV’s.
Neo Gold did a excellent restore and has the paint colours in this post, hope its ok to link another forum.
https://forum.arcadeotaku.com/viewtopic.php?t=45412&hilit=Konami+windy+restore
Are you playing it on a CRT? It’s pretty simple to tell if it’s 50 or 60 Hz,
50 Hz PAL will play in slow motion and have a letter box screen.
60 Hz will play full speed and full screen.
My guess it’s already been modded.