First, I totally believe you when you say those shells are seized in the arms. In the picture you posted with the puller, you’re set up to pull the wrong way. You can see in this picture what it looks like as the bushings are removed, you can see what parts are UCA and what part is outer shell here
View attachment 1716083539
Here’s a full breakdown, just for future reference, on the removal and replacement of the bushings.
Refurbishing Upper Control Arms (UCA)
Now, that said, new UCA’s. There’s really no need for offset bushings with tubular UCA’s. All the tubular UCA’s I’ve seen have at least an additional +3° of caster built in, some have 4. So you should be able to get plenty of positive caster with the tubular UCA’s just out of the box.
I have used offset bushings in tubular UCA’s, which allowed me to get up to +8° of caster with a set of non-adjustable Magnumforce UCA’s. But even I don’t run that much positive caster. And for how you intend to use the car any of the tubular arms you can buy should have all the caster you need built in.
