I agreed with everything in the answer - especially the use of trans fluid as a protectant/cleaner - EXCEPT the comment to spray the cylinders with WD-40.  WD-40 is 50% "Stoddard Solvent", re - mineral spirits.  It is used as a rust preventative, but it's really poor at it.  I know - I've used it for that and been burned by it.  That's mostly because mineral spirits is a solvent, not a lubricant.  There is only 15% light oil in WD-40.  

http://en.wikipedia.org/wiki/WD-40

If I was going to use long term storage (and I'm about to) I would feed the cylinders a good dose of trans fluid and rotate the motor with the plugs out.  I'll put fresh VR1 30w racing oil in it and pump it through using a drill.  Then coat the outside of the motor with light machine oil and wrap the thing up tight with plastic and some dessicant.