I can't comment on the differences between the two bourbon proofs, but the infusion process sounds right, although I'm not sure you actually need to shake it up every few days. Check it after a couple of weeks, then, if you want more of a vanilla-forward flavor, leave the beans in longer, checking every few days until you've achieved the level of flavor that seems good to you.
I've done this in the past using grain alcohol and was happy with the results.
“Only the pure in heart can make a good soup.”
― Ludwig van Beethoven