http://spinningwheels-sc.com/eatonm90refresherkit.aspx
This is the kit I used. It is a small family company but the people are very polite and ship fast. Your kit is missing the rear main case bearings that support the rear of the rotors. I highly suggest that you get those too because they are usually the first to burn up. See the link below.
http://spinningwheels-sc.com/eatonm90needlebearings.aspx
A press is required to get the bearings out of the snout and out of the rear case.
The snout pulley on the Thunderbird SC Eaton M90's is press on. Just get that big 3 jaw puller like you mentioned and you will be fine. If you press slowly then you won't marr the stock pulley so you can reuse it.
Pulling the front bolts out is not an issue.and separating the three main sections of the blower is a breeze for anyone with a little common sense and a rubber mallet. The middle plate contains the synchronized gears with rotors attached and all pressed together. There is no way for them to just fall apart, lose timing, or otherwise separate so don't worry about that at all. Once you have it apart you will see what I am talking about and understand why taking this blower apart into its 3 main sections isn't hard at all. It may take some whacks with the mallet and prying with a flathead screwdriver but once you have them separated by about 1/8" you can just pull them apart. The snout housing will pop off pretty easily too. Try to be a little careful when pulling the middle bearing plate/rotor assembly out of the rear main case. You don't want the rotors banging into and scratching the inside of the case as you pull them out. Once that is out you can set it aside into a plastic bag. All of the rebuild or porting that you can do are in the rear main case and the snout itself.
Just a note going back to your original issue of having a leak after sitting. Chances are that you just needed to take the 3 sections apart, clean up the mating surfaces, reapply some anaerobic sealant, and bolt them back together. But it isn't a terrible idea to rebuild the blower since you will already have it apart so you know it will be fresh after install.
I keep a pretty large personal library of articles and publications, etc of different things including Eaton rebuild articles. If you PM me your email addy I can send you some of what I have so you don't feel like you are flying blind. Some searching around in the internet should yield good info on rebuilding these units too.