Could you please post a picture of what you're dealing with? I'm trying to visualize but can't quite see the problem and don't recall spending that much of time to install the keepers in any of the valves. Having said that, patience is called for in the utmost and now you can attest to that. I recall losing a keeper in the engine and spent nearly a whole day looking for it . I simply had to find it - no options, as you don't want to imagine what damage a keeper floating in the engine would do.

Take it easy and no rush

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'05 E53 X5 4.4i, '97 E39 528, '07 E92 335i, '16 F86 X6M.