[jflem_also]

are you disc or drums currently?
if you have trouble at stoplights could be your vacum booster?

the 3/4-1 tons up till 91 or so had 12.6" rotors and would fit in 16" wheels.

I looked but can't find the old article, about tricks the old roundy-round guys would do to upgrade brakes.
they would mill the rotor off and keep the bearing and wheel mounting surface then put the separated "hat" brakes and go to bigger rotors. and run fixed multi piston calipers.

take time and some fabrication skills

my 71' has fantastic pedal feel to it, its was actually better than the stock pedal on my 2002.