I don't know. Seems that some of you make it far too hard. I have a level on the front of my fiver that shows how many inches I have to raise a side to get level. I have a few 2x8s that are cut long enough to fit between the wheels. The ends are tapered (45) and one is shorter than the other so I can stack three between the tires. This allows me to check for level, place the required amount of lift between and ahead (or behind) the wheels. I then only have to move the trailer a foot to 18 inches and we're level.
Also, on a tandem axle, by putting a 2x board (1 1/2 inches) under one tire will give you 3/4 inch of lift. No need to carry shims.
I will pull into a site and check for level. If needed I will move the trailer back a foot or so and place my leveling blocks ahead and between the tires. Then pull the trailer up on the blocks. By stacking various amounts (eg: two under one tire and one under the other for a total lift of 3 1/4 inches) I can level the trailer in a couple of minutes and get on to more important things.....like beer.