Always had good luck with 3/4 inch conduit linkage for steering and rudder spacing fastened with 1/4 sstl bolts, washer shims and locknuts which held the clearance so all of it could move freely and to top the steering system off it had 1 inch pipe from transom area up to the bottom of the stick which was 1 1/4 steel tube (1/8 wall thickness). Of course that was on a pure 1800 lb hunt boat from the 70's with a 500 caddi.
The rig lasted for about 20 years with only minor straightening problems when we slammed our flat 1/8 inch 7075-T6, 2 ft x 4 ft rudders into trees sideways once and a while when on a deer. That can get scary at planing speed in an inch of water on muck down in Area 3 S of the Alley.
Lot of fun back then.
Seems like nowadays if it don't look hi-tech and bought in a store or built in a factory folks think something ain't no good.
What the heck though state sales tax collector and many profiting love the new ways plus things look cooler.