Hi Brett and welcome.
Have a bit of a think first about what you might be wanting to wheel. Strictly car stuff, or perhaps bike stuff or even art? The latter ideally needs a wheel made to suit.
I've built 2x now. The first was a rehash of somebody else's home made efforts, but whist the machine works well enough for my needs, once I started having a go a bike stuff, the panel would hit the edges of the lower anvil cradle as the shape came on.
Solution was to build a second machine with narrower and taller than normal anvils.
I did a thread on here a few months back.
https://allmetalshaping.com/showthread.php?t=19785