yes, u-bolts. But also thinking to form the plate so it wraps around the triangular cross-section of the leading part of the arm and put a carriage bolt thru the face so it bolts to itself. I got bogged down with yard work today, but the Sub is waiting in the driveway, 1st thing on the 'To Do' list tomorrow.
'Unsprung weight is Bad' but I figure ~13"x6"x3/16" plate and bolts will only add about a pound and a half.
As I fiddled with some paper cutouts it seems a plate could be bent to sort of clip onto the bottom of the control arm forging and fit at an upward slope with the swingarm shape and a wide triangle tab could extend along the top of the control arm with a hole in the end that aligns with the sway bar end link bolt hole. That end link stack could hold the plate in place.
Just a very rough start. The steerign linkage will pass right thru at least half or more of the upper half of that paper area.
I'm thinking that tomorrow after I dismantle the sway bar, shock and torsion bar connections and can move the suspension freely without load, I'll use some double stick tape on the old lower arm and stick some card stock to it and start cutting it down for clearances to all the moving parts. Put the suspension and steering thru the full range of motion and trim off anything that makes contact or comes close.
Side benefit - I think such a plate will also act as a wind diverter, pushing air onto the brake rotor. The lower arm does angle towards the rear.
There's also a slight angle in the control arm, so a flat plate is a little tougher to do. Simplest would probably be two flat plates, one the shield, with clearance cuts and a slight bend up the middle. And then the anchoring tab triangle, with the point end over the end link hole and the other end with a 1" wide bent flange positioned to be attached to the shield plate. But that's a pretty weak design, an actual spearing by a branch would bend the thing. So a plate mounted to the bottom of the arm and bent up in the front would be a little stronger but take 3-4x more material.
The other design option is covering the whole bottom of the lower control arm but with its leading edge turned up and high. And it can be clamped to the control arm with some carriage bolts and some sort of clamp fitting designed to fit the top surface of the control arm, a la a coil spring / strut compressor clamp
/spitballing and ironically in stryder's topic as IIRC he's got aftermarket control arms, totally different shapes.
