I picked up a pair of Poseidon boards from eBay (many months ago) and I want to use them to build KT66 / 6L6 monoblocks using a pair of Acrosound 6.6k U/L transformers. I see from documents that there are slight circuit differences for the Mark III (KT88) version and the Mark IV (EL34) setup. For KT66 / 6L6 which version would be better suited? The boards are currently stuffed for the Mark III setup but, I would have no problem changing them if necessary.
Thanks in advance.