how do you get threw firewalls

If the car you are working on is an automatic transmission most of the time there is still a spot where the clutch would have gone through on a manual model. These spots are almost always the best just make sure you look on both sides and make sure you are not going to hit anything. I always like to start with a small bit and then work my way up in size with a unibit. There is no real easy way to do all cars but just be careful and in time it will get easier and easier to find a spot.2008 Scion xB

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