DIY Gear Lube Change, seal question

[bauerej]

I had an SE116 lower unit installed on my 4.3L Mercruiser Alpha1 Gen II recently, and the unit came with instructions to change the gear lube after 20 hours.

I am considering trying that as a DIY project (I have a lot of car repair experience, but this is my first boat). I found instructions for this procedure at:
http://www.sterndrives.com/changeyouralphagearlube.html

My engine has the remote gear lube reservoir. My questions are:
1. This procedure recommends replacing the seal on the drain plug. Is that necessary after just a couple months / 20 hours? If so, what is the recommended source (Does SEI sell just this seal) ?
2. I realize I will have to get a gear lube pump to perform this. Are there any other special tools, considerations, or recommendations around doing a gear lube change?

[Tech Support]

Changing gear lube is something you should be able to do yourself. It is recommended that you change the seal on both the drain and vent plugs. This is because they damage easily and are inexpensive. You can get them at your local Mercury dealer. Other than the lube pump you will not need any special tools.

Tech Support