Wolfgang, I just spoke with Don at the Bird Nest. He said that the 1961 rear suspension was a one year only set up, and they found it did not work well and changed it on the '62/'63's. He said that he does not have those parts you referenced and they are probably going to be hard to find. The parts breakout you provided is for the '62/'63 years and not the '61 year. We can only hope that in 1961, they were still using the 1959/1960 Squarebird set up. Hopefully, John or Carl can tell us about that.