Well, I tried with a tied halter, but the sheep really hated it and struggled to get free. A proper head-yoke might have been ok though.
However, I went to a different feed store to normal today and they had an AIE docking crate in stock. It had turned a bit green and must have been sitting in their yard for a while, so I managed to bag it for just over half the list price
. Definitely my strangest ever impulse buy, but if it saves me from another herniated disc, hopefully money well spent!
I ran some ewes and lambs through it tonight to check, and I think it will do the job nicely. The width adjusts easily without tools, and it's perfect for doing bums, undercarriage and back feet. It can also be used for injecting and drenching. Front feet are a bit of a challenge since the sheep stand quite far forward in it, however it was possible and I think it will be easier if I raise the crate off the ground a bit.
I also think I'll be able to make a footbath for it. This may require changing the back doors so they open outwards rather than inwards, but that looks easy enough. I don't think it will be any use for sheep with horns BTW, but I'll report back properly in due course....