Davie, thanks for your further explanation. It has been a source of bewilderment (to me, anyway) as to how the 2 towing wires were laid out. I never thought of such a thing as a "towing block"....but it now makes sense. Alas, there are so many "unknown unknown" things here (to paraphrase a certain American) that to make sense of it all I think I'd have been better off and wiser to build a 1:1 model! But in the absence of that, I'm sure that other sidewinder builders (and fans of same) will have learned a lot from your input to my ignorant questions. Thank you. Bryan.