Brake Booster Removal/Install

Tomorrow I plan on changing out my brake booster for a new one and am a little confused. My 74 Dodge chassis manual says there are four bolts under the dash that will need to be taken out. However on my 74 Dart my booster is attached to four bolts under the hood with access right to the brake lever. Is this an error in the book or am I missing something? Can you guys give me any tips in order to do this thing right?