If you have a hand-help vacuum pump such as a Mityvac, you can pull vacuum on the WGAs and watch the rods move. The front WG rod is nearly impossible to see - much less touch or remove - without pulling a couple of things apart. The rear you can see easily.
I've seen one turbo where the WG pivot arm that goes into the turbine housing was so worn and sloppy that it bound up. When vacuum was applied, the WGA rod would move about 2-3mm and stick. If I stuck a prybar on it and gave it a shove, it would work. Only solution was a new turbo.
E92 335i/6MT Dinan Stage 3 intercooler, oil cooler, intake, flash.
E28 M5, R171 SLK350