Pics always help. I assume the amp looks a lot like this:
Sunn made several 2x15" speaker cabinets. What does yours look like? Also, there should be a plate on the back with a model on it, something like 215S, 215B, 215BH, or the like. Older cabinets didn't have that, such as the 200S. Reason being that, in the early days, amps were sold as a package deal, head and cabinet together. Later, in the 70s, they went to a "mix and match" concept, where the amplifiers and speakers were sold separately, so the speakers needed their own model names. So, again, pics would help.
