Oldpatflr,
That is certainly a beautiful plane you have there. Sorry I cannot help you with any information, but I asked about this plane a year or so ago and RFJ came up with a little infromation if I remember correctly. The reason I inquired about it is that I had been talking to a very good friend who I fly with about the plane. He has been flying for many years and is the best RC pilot I know. Anyway, he said he used to have a Mistress with a YS-61 2 stroke and he told me it was the most neutral and honest plane he ever built or flew. He said his plane would stay in any position that he put it into, until he moved the sticks again.
Good luck at the contest with your Mistress. Let us know how it turns out for you.....

David