Nothing hard about installing the Bean Mod. I compare the difference to the OEM points to the difference between the old mechanical breaker distributors to the modern breakerless ignitions. I still have one of those dinosaurs and get to replace them every 8k miles. Refreshing to upgrade the Mitsu pump to modern specs. Not problem with water getting in if the upgrade is done properly. If not, the points will fail too anyway.
DISCLAIMER: All observations made in this post are mine and based solely on my own anecdotal experiences, and may contain large doses of facetiousness. YMMV, of course. You are "on your own", and I take no responsibility if someone tries anything in this post and gets into trouble with the law, damages their person or property, or goes blind. Take everything you read or hear "anywhere" butt especially on the Web with a large dose of salt.