Do you happen to know what year(s) I could use for a 65? I seem to recall a lot of posts regarding collapsible and non-collapsible columns being incompatible.
Can you tell me what you are calling the coupler? Is this the servicable part with the pin and plastic? If it is a matter of a difference in the splines on the end of the shaft then I can cut a manual shaft and mill the proper splines in the end of it or, if this was not practical maybe I could take the end off the power steering shaft and turn a "male" pin so it would mate with the PS shaft "female" hole I could bore in it and then pin the two together with a taper pin. This would be as strong as a single unit and I could even weld the ends of the taper pin to be 100% sure it wouldn't come out AND bevel/weld where the two parts meet. I would have faith in this much more than a simple butt weld.
Thanks-Howard