There used to be a guy on the audiokarma site under Mondialfan (Kevin M) who did them. Also Ken Ealey, tho he seems to have disappeared. The Mondialfan guy also sold a kit on Ebay. I got the kit last year and had a local tech do the work on my RL11. It was worth the money as it became much smoother, less bright on highs, got a darker background (very quiet pre) and became more transparent and dynamic. Stopped me from buying a new preamp as it really was improved. There are a couple of sites where you can find via Google upgrade/mod recommendations. My sense is a good tech can do them easily. PM me if you want the Ebay guys info.
