Solid strut rod bushing on stock strut rods...good idea?
Delrin is a no go for strut rod bushings. As already mentioned, they have movement in multiple axes so while you want them to be stiff to resist forward/aft movement on the LCA you also still need them to flex to track the up/down movement of the LCA. Otherwise you’d lock out your suspension travel. That’s why the adjustable strut rods work well, they resist forward/aft travel while allowing for free up/down travel.
I don’t know if they have adjustable strut rods for that application though. They’re not terribly difficult to make, if you take the measurements at the K frame you can have a set of pillow blocks made up for the K. The rest is just a heim and a threaded tube, you can buy the later as generic parts from AFCO.
Or just source an earlier k and get rid of the ISO stuff. In which case, I’d buy your LCA’s if you want.
I've always wondered if steel cable would work instead of rods.
Stupid idea.
Yeah that would do the opposite! It would allow forward/aft movement of the LCA under braking/acceleration, allowing for significant caster changes. Strut rods are also known as “brake reaction struts”.