Brake Booster

2003.5 Mazda Protege5
Alright my girlfriend's car is closing in on 50K miles and I have an obsession with seafoaming engines and I have always done it through the brake booster line including my 2.5L Duratec V6 Cougar that I had before my protege5. My question is where the hell did they relocate the brake booster line to? I cant seem to find it