I never actually measured just marked the cardboard off the old rusty one and trial and error cut the cardboard template until I found it would be the right length. They are fully clamped shut, when I get new poly bushes I'm hoping that fully shut position works without any slack. In which case they might need to be shorter in length

If you've got Polybushes I would look at ensuring correct/custom fitments to them. I used an old small CO2 bottle on the vice to bend the big curve and a wheel wrench for the small.
I'll try and measure the cardboard templates tomorrow and PM you

I was actually admiring the work on your car earlier and interested in how your rear beam turns out as I will be doing similar work.That rear arch repair is impressive
Another pic.. Man it looks rusty but hopefully this summer it won't be
