IMHO, Peen them.
After a lot of trial and error and a lot of questions on here, I have a method that works without fail.
To me, the pins should show NO TRACE of their existence, and NEVER come off.
I use 3/32" or 1/8" pin depending on the size of the knife.
Let's say 1/8"
I drill the holes with a #32 drill bit, and then ream them with a 1/8" reamer. I drill three holes in a triangular pattern (thanks Jerry).
After I have all the holes drilled and reamed, I adjust my drill press down to the slowest speed and with a small, triangle Jeweler's file, I taper ream the holes (thanks Alan).
For the pins, I cut them so they stick out about 3/32" out of each side of the bolsters.
I round the ends of the pins with a fine belt, then buff them lightly.
Then I clean the whole shebang with paint thinner.
Now put it all together. You should have bolsters that fit tightly against your blade with very snug pins, reamed outter holes for pin expansion, and CLEAN CLEAN CLEAN.
Next I start off with a 24 oz. polished ball-pein hammer and start working my way around the pin, gently snugging them up more.
Finally I move to a 3 lb. Hammer and hammer the sh** out of the pins.
This takes a while, but it works. You will NOT SEE MY PINS.
Just my $0.02
Nick