I had the factory KT88 conversion procedure manual mailed to me from Luxman. I can mail you a copy, email or snail mail. I converted my amps some fifteen (20?) years ago, and have been quite happy. The old design had the tubes right on the hairy edge of the operating envelope, that's why they went through output tubes and needed frequent bias adjustment. With KT88, you set the bias once (check after a few hours of break-in) then forget it. I have rechecked the bias after five years, and it remained rock solid. I have since upgraded the caps and resistors, and true to what Shussbliss says, I heard noticeable improvement.