>>>>>>What are the two upper links called & what is their function?

By all the part microfiche I looked at they are called "link".

>>>>>>We know it's legal to add a center link while leaving the two OEM links in place with air/foam bearings. The upper links are called link traction bars otherwise the center link could not be installed.

Not true, You can add the center link because you can add/substitute traction bars. The foam in the upper links is because bushing material is free. 2 completely different rules.

>>>>>>>>IF you are free to take the link bar, and gut the rubber bushing and replace it with one of your own under the free bushing rule, then you are free to use offset bushings, correct? Of course.

Not true. Bushing must be concentric. Why? because the definition is a reduction of diameter. You are not allowed to change the end result of a bushing only its material.

Bushing is defined in GCR: A sleeve or tubular insert, whose purpose is to reduce the dimension(s) of an existing hole.