i just sent a few people seeds.
what i did was squeeze a fruit while pressing down on a long thin piece of paper towel.
maybe 1/2 in to 1in wide... a few inches long
it will dry in an hour or so, less in the sun.
you can cut up the paper towel in very fine/thin strips
each strip having several seeds - maybe dozens
Or, after they are dry, you can use a knife or razor blade to scrape them off.
If i were to do it this way, i would use loose-leaf type paper
instead of a paper towel.