As it turned out, the valve stems weren't threaded into the wheels, just corroded. Surprisingly, the hole diameter was slightly smaller than the standard .453", something like .4". I could have reused them, but the gaskets needed replacing and I was unable to source them. I ended up using these valve stems that are the small valve cap diameter for the full length. The tapered gasket centered them in the hole and the flat washer was a good fit in the well.
https://www.amazon.com/gp/product/B01MA1SCFU/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1