He has no 38" scale instrument, but he uses (at least on the 4s) Dean Markley. I'm not a huge Dean Markley fan, so I'd look into Elixir or DR (two of my favorites). I know that for at least the six-string fretted, he either uses or used Carl's strings. I don't know about the legendary "Rainbow Bass."
As for measurements, I'd kind of like to know the length and width of the body blank(s) and the neck pieces, the truss rod info, and the width of the fingerboard at both nut and heel. That is, if it's not an utter inconvenience to you. Thanks.