Paul M. Cook wrote:
When selecting fruits, cucumbers in this case, does it matter if the
fruit is not the best the vine has produced?

No. What matters is the genes that the fruit carries (so the progeny will
be good) and that the fruit is ripe and the seeds are viable.

I have my last cucs
coming in now. I plan to save some seeds for next year. But they are
all fairly small fruits compared to my earlier harvests. Does it
matter?
So you just clean them and then dry them, right?

Yep

David