changing from a single bowl master cylinder to a double bowl

[WOLFMANmike]

ok guys so here is the question right now im a single bowl 4 wheel drum truck .. im keeping the drum for now . but i want to switch over to a double bowl master non Power so the question is this 1 what year master will i need and will bolt right up without having to cut or modify the firewall ? number 2 i have the stock pushrod now .after putting on the dbl bowl master will it work with the stock push rod ? or do i have to buy a adjustable push rod ? if so can you give me a part number and the place to buy it .. and number 3 what do i have to do to the line to make it work with a dbl bowl master ? and lastly once this is done and i change over to a front disk brake set up . im still not going power can i still use it with the disk brakes or do i need to but a whole new master and change everything lines and push rod and all ? thanks again for the help