Well, the skid bars are kinda like the old 'curb feelers' from the old days...
They are meant to WARN you that you are hitting something... They are not meant to support the whole rig once you hit them...
It won't do any good to strap on some rollers on those things, because they will only reduce your clearance even more, and they are still just 'curb feelers' anyway..
Now, if you want to remove the skid bars and put the wheels in their place, than you might okay, but now you are asking the trailers frame to support your rig on an angle with weight on it that it was never designed to handle..
Taking the driveway at more of an angle might help, but if the angle is just too much, it's just too much for your rig and I'd either try for another place, or try a different angle.
Good luck!
Mitch