There used to be a vendor in CA that built a nice little 4 wheel cart for holding a finished Flathead motor. It used the water pumps and the back of the motor. I'm looking for one for an 8BA.
This guy in Laguna Beach, CA? Here is the link from the Ford Barn: https://www.fordbarn.com/forum/showthread.php?t=278943&highlight=flathead+engine+cradle
Unistrut would be good but 10 minutes with the tape measure and five minutes digging in the I'll need it some day tubing barrel should probably produce the frame and a plan to build it Plus maybe about an hour to weld it up if you take a couple of breaks between welds. This very obviously doesn't fit a flathead or look like the one the guy has/had on Ford barn but I'll show him some respect and post a generic stand for concept. With the proper uprights to hold the flathead using the water pump mounts and a setup to hold it at the back of the bellhousing you have your stand. Probably the biggest outside cost is a set of casters if you make use of left over material. Personally I'd make the stands for the front to bolt the front to and then level the engine up and make the rear stands. probably making the stand the same width as center to center on the front mounts.
I have one that you can have if someone can come by to pick it up and ship it to you. I bought it and had to modify it to fit the bell housing on my 8BA. The mods were to split the center to add length and I also added wheels.
Don't have a motor off of one but there use to be an outfit out of Arizona I think that made a nice frame and the middle had angle iron supports that slid to and under the pan. Maybe I can get a picture of one of mine.
Seems strange that we are telling the guy who can fab just about anything how to come up with a simple engine storage cart for a flathead.
I have 2 flatheads in my garage, mounted on custom 4 wheel carts. The carts were formerly the bottoms of shopping carts. The baskets were cut off, the engines set on the base and a section of 4x4 placed across the side rails and underneath the forward section of the pan. They roll everywhere easily and don't complain. A dear departed friend of mine made them and others from abandoned shopping carts found in alleys and parks. They are the perfect engine carts and adjustable for any engine by using different lumber to brace them as needed. One detail that is funny. My friend was a sheriff's deputy in Imperial County here in California. He would find and modify the carts as he needed them. He was retired and one day his daughter was at the local parts house and a couple of deputies saw her. They came up and said that they knew her dad was cutting up abandoned carts and then dumping the baskets off anywhere he felt like. They told her that they weren't going to turn him in but asked her to please tell him to be more careful where he dumped the baskets because people would complain and file a report causing them hours of paperwork! Every the worked out because he got more choosy on where to dump the baskets and after he passed, somehow, nobody found more cut off baskets. Now I am not saying how to obtain these great engine carts, only warning you that if you do, be clever with the unused portion disposal !