67 Nova Heidt rear 4 link

[79 Camaro]

I'm running a Heidt 4 link rear in my 67 Nova. Although not really a dedicated pro tour car I'd like to replace the 4 bar ends with johnny joint type rod ends.

Better articulation and no groaning like the current poly bushings. Do I or can I run johnny joints in both ends of the 4 link? One end enough?

Same for the panhard bar?

Thanks.