I use a white GE Silicone II for most of the sealing and a Dicro sealant for the roof.
I have been also replacing alot of the sealant/caulk on my unit and have found Minerial Spirits good for removing just applied silicone that havn't cured, but didn't work well for me when removing the older/cured stuff. I have used GOO Gone, wiped on with a paper towel, does a good job in helping to lift/loosen the silicone after it has been partly removed. Haven't found anything that will make it jump off the unit but the Goo Gone has helped. It hasn't affected the painted surfaces or the fiberglass on areas I've done.
After the caulk/silicone has been removed, I use a general purpose cleaner...I use 409...to spray and clean the area. Before aplying the sealant, I will wipe the area with alcohol applied with a papper towel.
For tools, it's plastic scrapers, a 'dull' parring knife for hard areas and a fingr nail or two. Nothing to sharp but have used a flat blade razor a time or two but have to be careful because it will cut quickly.
I did a picture post on the Excel Forum, pg 1 - post #4
, when I was caulking my compartment doors if your interested.