I use simple green usually and sometimes purple power. (Simple green has worked better IMO) cover up your air filter, dizzy, alternator, and starter with some plastic bags. Then wet the bay with medium water pressure. Spray the degreaser or soap of your choice and cover the whole bay. Let it sit for a few minutes and then go ahead and start scrubbing both fender sides and firewall with a soft brush, you can also try brushing the motor and any other parts you want cleaned. (Just be careful not to wet anything that shouldn't get wet) you can rinse and spray more degreaser if needed to any spots you missed. finally rinse off the bay and dry as much as you can. Start up the car and let it run for a few minutes, this should help dry the motor and any electrical cables that got wet. I managed a detail/ carwash and this is the way we did it. Good luck man, hope this helps.