I am getting ready to convert my 2wd to 4wd. I was looking over my donor truck and noticed the brake setup on my 2wd is different than the 4wd donor truck. The 4wd has both calipers on the rear axle facing rear. The 2wd rear axle has the left brake caliper facing forward and the right brake caliper facing rear. Why would this be? I was hoping to just add the blocks under the axle and not switch it out completely do you think this is a problem?