RE: Dave Patrick Ultimate Bipe??
Walt,
If the span is 54" it's not a DP. The DP has 4 aileron servos while the Goldberg has one (using bell cranks) or 2.
The interplane struts for the Goldberg are die cut lite ply plus die cut balsa. I might be able to send you a copy of the GB plans showing the struts if you like.
Ray