Thanks, we're using the Pomona 72918 banana plug, Mouser 565-72918.
Need to finish up the solder SMD plug-in PCB that plugs into the base PCB like the PCB with the Lever Arm fixture shown.
These 3 PCBs will allow the use of leaded components with the ZIF socket, non-soldered SMD with the Lever Arm Fixture PCB which fits on top of the base PCB (with ZIF removed) and finally smaller soldered SMD PCB which also sits on top of the base PCB (ZIF Removed).
We'll post the design files after we order/get the PCBs and get things assembled and tested. Not sure how well the SMD Lever Arm fixture will work since it's based upon pressure contact of the SMD which likely will be highly variable, but worth a try!!
Regarding your components from AliExpress or eBay, seems it's always a question with components from them. We've had sub-par LM358s, a LM399 that drifts, sub-par TI switch, and other questionable components. Had good results with the usual US suppliers Mouser, Digikey, Newark and even Chinese LCSC.
Edit: Here's the Solderable SMD Fixture, this plugs in by the 16 pin header and mounts on top of the Base PCB which has the Banana Jacks for the Tek 577. The Kelvin feature is utilized to help remove the connector and trace effects. The PCB is small (0.9 by 0.9 inch), so should be relatively cheap.
Best,