Hello and welcome TNF,
I brought my wishbones but the curve you mention is the same as the one that I did to join the cross piece to my roll bar.
Bodged the first one then someone pointed me to a web site that has a program which allows you to print out the curve on paper which you then wrap around the tube, mark out then cut. I used a flap disc.
I know the tubes for the bones are a lot smaller than my roll bar cross piece but I am sure with some fettling you would get there.
Cheers Ginge
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