One of my winter projects is to clean up all the electrical connections under my dash there starting to corrode a little bit. i was going to take them a part clean them with a wire brush and grease them to prevent more corrosion but what type of grease should I use? I know wd 40 works but don't really want to spray the stuff all over the place and it doesn't last that long anyway, any suggestions.

You can buy a tube of Dielectric grease at an auto parts store... it's really thick... silicone.... won't drip off.... how well it will work... don't know.. give it a try. It's the stuff that the car makers put on their underchassis connections... Looks milky in color. Good luck. I would suggest that you clean the terminals first... then apply the grease.

You could try spraying some electrical contact cleaner on them.

After you clean them up cover all connections with Liquid Electric tape they sell it at marine stores puts a nice coating on screws and connections I wouldn't put it on the fuses though

Liquid electrical tape is good on screw connections, but if these are connections you're planning on taking off (Like spade connectors), use the silicone grease. I've used it for years and never had a problem. I even used it on my trailer bulbs, and it works great. Years ago I worked for the NYC subway system, and that grease is what we used on the electrical connections on the trains.