I have used a light oil on guide pins but more as a cleaning agent. Wipe with oil then rub it off with a rag. Just enough to help assembly not enough to gather dirt and dust.

The last set I did a week ago the pins were in good shape no surface wear or corrosion I just wiped them down before installing.

Back on topic; how sure are you the pins stripped and you didn't just round off the fastener head? I believe those are 7mm. If you tried to use 6mm it will likely tighten and slip and feel much like a stripped bolt.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)