I have a 2004 std, S19 with a 3" lift. I have to use 6"x6" blocks under the rear stabliers or they would not touch the ground. My front landing gears will reach the ground but they are a bit wobbly. I carry blocks for the front landing gear which really stablizes the trailer. A friend of mine who has a 3" lifted S19 blocked his entrance step out and down several inches. You might want to just go with a two step arrangement if you lift your trailer that high. If the trailer has 13" tires
you may want to go with bigger tires
and rims that may be all you need if the trailer already has a 3" lift.
I just turned the bed so our head is at the front of the trailer and added steps for the front bunk, best mod yet. Good luck with your new trailer.
My trailer's upper deck lower edge is 56" when setting level. My frontier 4X4 truck bed is 50" from the ground empty, and I have plenty of clearance. If your trailer has a 3" lift you should be OK. When you put the trailer weight
on the truck the bed should drop at least a couple of inches.