As for mounting the jacks, I put a gusset in place, cut the top off it and then welded on another flat piece of steel. I drilled 4 holes in the piece of steel and then bolted the jack on. This way if the jack goes on me, I can easily replace it. This is where the 5 foot piece on the base meets the bottom parts. There's also a picture of where the jack mounts to the top.
I welded all the castors into place. I was going to bolt them on, but decided to weld them.
Here's a bunch of pics with the car on the rotisserie.
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