I did it as a newbie and it was a really easy job. The only difficult parts are buying correct inner seal, removing old seal and taking meticulous notes as to which parts were where and in which direction. If in doubt take a lot of pictures. I bought mine on eBay I believe it was the NOK BH3888E seal. I just checked and there's a lot of auctions for them, one auction even comes with outer O-ring so you can replace both. I actually thought the whole process was cool and fun, brings back memories. I'd do it for you for free if I could

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Use this video. Several things I did differently from this video (all of this is at your own risk):
1. If you take the cap off and can't see the screw for the rotor if your rotor uses a screw, I wouldn't bump it until the rotor spins where you want it. I'd just take the whole thing off. I don't risk messing with anything electrical with the cap off, there's a safe way to do this without damaging the coil but I don't know it and don't want to bother since once you remove the dist the shaft spins freely anyway and you need to remove the distributor do this anyway.
2. Leave the wires unmolested if at all possible. IMO the person in the video removes some things like the magnetic sensors that he doesn't really need to remove. Although like him I did remove everything so I can clean the inside out without hitting the magnetic sensors with brake cleaner. If you're going to remove anything inside that has wires, in my experience with two internal oil leak distributors the oil appears to harden the wires and due to age the wires appear to crack on their own exposing the metal inside. Try not to twist or bend the wires carelessly. Also the ICM connectors don't need to be removed (I don't believe he removes them in the video), leave them on since the boots tend to crack even easier. Another thing you should do is inspect the wires for wear. Aside from cracking, on one of my distributors I noticed the wire had moved over time to where the shaft would spin and contact it. This wore a flat edge into one of the ICM wires and exposed the wire inside. This distributor was causing sudden shut off while driving. I assumed it was because the spinning shaft would contact the exposed wiring and short the ICM signal out. Look for this (you'll see a flat edge ground into a wire) and if you see it you might want to deal with it. Either bend or move the wire away from the shaft or coat it in something.
Good luck!