i would think that the 114/115 would be your best bet.
steering box would probably be in better shape because:
these cars are lighter than the 116/123s. they dont roll into
curves like the 116/123s which would add stress to the steering mechinisms . they were slower. 107s are rarer with v8s that broke the subframes and who knows what else. all in all less stress to the box.

in my opinion the 115s take curves and straiteaways better than
the 123s

don