Concentric Neutral & Spliter Box

We're on a farm and we are going to change all our secondary from overhead to underground. What the guy from the power company suggested is to move the transformer and the meter to the road. They're replacing the main line, so they'll do this at no cost to me. Then the secondary will run to a splitter box on the side of my shop, and split off to the shop, the house, and a pumphouse in the yard.

Two questions. The first is, what is the best way to isolate the box, which is metal, from the metal siding? I'm thinking just wood. The second question. The secondary is USEB, which has a concentric neautral. So when that is twisted and comes into the box, is it insulated somehow, routed so it doesn't touch the box or what? Again this is just a splitter box and not a panel.