When I wash mine, I drive up a pair of ramps to lift the front end up in the air to get under the truck as well, and then let it sit over night, to allow it to cool to the ambient temperature. I learned this the hard way due to condensation, when I washed my gasser for the first time years ago, allowing it to cool first but was still warm. I had to remove the distributor to dry out the cap and points (yes, thats how old I am) so I could restart it. It did the same thing a second time, and so I dried it out again and let it sit open for the day. From then on, I let them cool to ambient before I hit them with water of any pressure. I also have only used Gunk cleaner except one experiment with simple green when it first came out and didn't like the results. I then use compressed air to blow the water/moisture off of connectors and related equipment, (this helps in eliminating water spots as well) then let it sit a couple of more hours with the hood open. Also a little more advise, I close the hood after applying the cleaner and rinse off any over spray on the fenders and windshield before I let it soak with the cleaner.