Hi, I have a lead on a SVT-HD serial number 1007. I have done some research and believe that this was made by Dave Ryan, but it isn't an official part of the 500 SkunkWorks models. I found a forum on another site and a guy had an SVT-hd serial number 1112 with writing inside saying "tested and built by Dave ryan" SLM 500..... I believe the seller said that Dave Ryan has his writing inside as well, but we discussed a lot and I don't remember for sure. Is this serial HD-1007 a Dave Ryan post official "Skunkworks" bass amp? I read that they went to japanese MTI and that components were switched out, etc. I heard from the guy selling it that Dave Ryan and co. had parts around and built several more "skunkworks" type amps... What is the value of a great condition, recently gone through, working SVT-HD serial 1007 amp? What should i consider paying for it?