Thanks for the heads up on "priming" the larger cooler. I already know to do that, not my first rodeo. Used to be a big gearhead in high school and when I was too poor to take my vehicles to a shop.
I went ahead and ordered a gallon of the Ford Mercon LV to have some on hand. I also plan on changing out the power steering fluid and the front differential fluid since they both take Mercon LV.
No worries, I figured, its more for the guy down the line who searches for the saudi style trans cooler and stumbles onto this thread.
I changed out the fluid on my power steering pump when I went to the GJ Motorsports filter and cooler. I started with my garage turkey baster to remove the fluid and then after like 10 minutes I said screw this and went to the West Marine and got an oil sucker. Works great on the jet ski too lol.
I didn't know that the front diff was Mercon LV. I would have just assumed it was 85W140 or something to that effect.