Using a Floor Jack as a Transmission Jack?

I have a trans adapter for my floor jack. It does require very tall jack stands. I bought tripod scaffolding footers from industrial surplus place and welded channel iron clips on their tops. The first 4 are a little shorter, painted brown and got 4X4 channel iron clips but the frame rails didn't sit down in it well. The next 4 got 5X5 inch channel, and painted yellow. So there are now 8 stands here.
Jack doesn't lift that far so I have to get er up on the short store bought stands first, add spacer, and go again. Too much labor for this old man today.

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