XM800W (20mm autocannon, not sure what turret WG can slap into it) from MICV-65 in 1965 Other American wheeled projects armed with a cannon were the: Later variants would have the Stingray turret the same way that OP's proposed tier 6 M38 Wolfhound would technically be an M38 chassis with a Chaffee turret to be viable at tier VI. Even the LAV's were a private initiative, though I'd peg the 90mm versions to be the late 60's at the earliest if outfitted with the low-velocity 90mm cannons as seen on the German LT line.

Truth be told, the 50's and 60's didn't produce that many wheeled vehicles only when South Africa in the '70s proved that a wheeled combat vehicle could be combat-effective and still be cost-effective did the M113-centric mindset dissipate. it wouldn't even be put anywhere near the desk of consideration The tier 9 and 10 are way too modern 1985 for the first prototype of the LAV-600. Having a quick look into the years, the LAV-300 at tier 8 might be pushing it at late 1970's, but I would say it's acceptable with the UDES 03 being early 1970's.

Modern american light tank 2018