I am looking at a SWR Goliath III. How can I tell if its pre-Fender or not? It's got a silver grill and one slot port. I haven't been able to look at the back so I dont know what it says there. Should I look for any telltale "made in" or "made by" markings? I am thinking of having an SWR stack of cabs and a Mesa stack. Then just move the Mesa Bass 400 back and forth. Horses for courses. of course.