Those pieces belong to a special kits that enclosed the battery box. The long piece sealed between the upper floor and the lower bracket that the battery sits on and the small triangle piece filled in the back section. The piece with the hole looks like, where the fan/ blower mounted that blew air into the battery compartment. There are a few pictures of this in one of my picture ablums on the surface zero site. I will see if I can find it and attach it, if not I can take a picture of my halftrack.