The problem I have with the engine stand method is the wheel spread is to narrow with very small casters but the basis is there to build off of.

I saw one for sale at the Year One gig at Road Atlanta, it was about $1100 with cylinders but don't remember the brand. I've thought about buying one, could use it and probably sell it for a few hundred less than new when done. The price of having the right tools for the job.

A home made one might be a tough sell but it could be scrapped out since you wouldn't have much in it. If I had the time to build one, I would, but I have no place or reason to store it when done.