my truck wont stop!!!

I finally drove my bucket about and hour ago after being parked since november and being body dropped for last month and ahlf. but the fucker wont stop. I have a Chevette brake booster and master cylinder and it seems like the master cylinder doesnt have the volume to stop the truck. the pedal is on the floor before it even thinks about stopping. does anybody know if there is a nother master cylinder that will fit the chevette booster? i heard a master cylinder form a 98-up s-10 will fit but dotn know for sure. i know mine doesnt. help. stopping can be one of those important things i might need to do in the future