Conflicting info on levelling with stabilizing jacks or not.

Carry 2 pieces of 2" x? (width of tires) and 2 pieces of 1" to adjust side to side. The large plastic legos only work on firm ground. Soft ground ...you will crack the blocks. Also carry 4 pieces of 3/4 exterior plywood to put under the stabilizers when on soft ground. Also carry a 2" x 6" x 12" long to use under the tongue jack.

From the model trailer you have, they are most likely stabilizer and not jacks. Just run them down to where you are nice and snug. You can use them to make very slight about 1/4" adjustments.

Ken