So I've had this Sorado for about 7 months now and am absolutely in love with it. As I'm pretty sure that my particular specimen has the original power tubes in it, I've decided to switch the originals out for Sovtek KT88s. When I began researching what type of new tubes would be best, I noticed a few peculiarities about my particular amp: First, on the inside left (from behind) the yellow sticker that has the tube configuration information says that the power tubes are originally kt88s. From all information I can find, this amp came with 6550s originally. Second, my amp has a third, smaller transformer of some type next to the power tubes, which I have also never seen on any other pictures of this amp. I was wondering if anyone else had encountered something like this with their Sunn, or if they know of a particular model year or something that had these. I'm reasonably sure this is a 1968 model because the chassis is signed and dated 5/14/68. I've attached pictures, thanks for your help!
(Sorry, I couldn't take one of the tube layout sticker because of my bad camera)
