Ok....so small bolt pattern vs big bolt pattern infos !

Mopar 11.75" Front Disc Brake Kit (Stage 2)

ok so if i get this right , i can install that on my 69 valiant and its a bolt on thing ? and im into a larger disc that fits a 15 inch steel wheel and 4.5 bolt pattern right ? that would be amazing , my duster was a disc brake car and my cuda too...never did the a body swap honestly