By the way, you've got the "nom de net" name the resident ignition specialist should have. Herr Sparky is great.
The original steel bushing was just to contain the rubber. If you machine your Delin down to fit witnin the old outer bushing, and the old bushing is smooth and round, you're okay.
thanks...i can only afford to to this job once, so i'm double checking everything. i measured them at each end and found some difference, but very little (0.004"), and that could just be my cheapo calipers. so i think i'll be able to make 4 identical bushings...
The type 4 control arms tend to be juuust slightly egg shaped. On mine I made both about .010" oversized and just custom sanded to fit. It was not too tedious.