It shouldn't be to difficult, the mast on a 22' sailboat generally isn't that heavy. You and your 2 freinds should be able to lower it easily.
Are you going to take it completely off the boat? If not, you need to have some sort of spot to rest the mast once you lower it, dont forget.
Since you said you will be repairing the boat yourself I take it that you are going to put alot into this sailboat. One thing I would recommend is a hinged mast base or some sort of a base that would make this easier if you ever want to lower the mast again. It could also help when the time comes that you raise the mast back up.
Check out these mast stepping videos
at my website, they show you a few different ways people step and un-step their own masts.
Also, I see you said that you plan to do the repairs to the boat yourself, well go check out the sailboat projects section at my website, I bet you will find it useful.
Good luck with your boat!