That one on the S-10 is clearly not for that truck. Warn had a kit specific to that truck that matched the lines much better.
Warn had several different variations of Trans4mer back in the day - but the winch carriers were limited - I believe if the distance between the uprights is 25" on the inside it would be the correct grille guard.
Warn made Trans4mers for everything in the late 90s (Isuzu Amigos, Toyotas, Ford Rangers, S-10s, fullsize square body Fords/GM/Dodges, etc..., then Mike Warn sold the company in '99 and investors started ruling it vs. enthusiasts. (I was an engineer there from '99 - '05)
That is a newer style winch plate - the older ones had a larger front face for mounting the foot forward winches (M12, etc...) (Similar to the picture of the Dante's Peak truck)
I'm assuming those frame brackets would not be correct - you would need frame brackets to "bolt" it right on. It is tough to tell from the pics, but it looks like someone did some creative welding in the bottom mounting area on each side.