My Clubman is in its sixth winter up here in Michigan snow country. We get five months of significant snow and thus the MINI brings in lots of sand and salt with the packed snow, many times each week. I keep her looking new outside, but underneath the motor there is some rust and corrosion that is progressing. I spray underneath more than twice a week, but I'm not sure I'm hitting the right places. I have never opened the hood and aimed down, but behind the engine and front wheels is the disturbing rust and chipping paint of the frame. I'm not sure how to describe it, perhaps the aft engine mounts. There is also rust surrounding the front ball joints. I try to get it by aiming up behind the front wheels crouching from the side.
So, my question to anyone who knows how to best deal with this is: precisely where is (are) the best place(s) to aim a spray? Perhaps I could spray under the bonnet on low pressure? Does anyone else fight rust in hidden places like this and if so, how?