port size on master cylinder?

[THE BOSS]

i have a 1972 1/2 ton 2WD cab on a 71 4WD chassis, it had 6 lugs axles and changed to 8 lug GM axles.

the brakes are poor and it is believed the booster is not functioning.

i bought a booster with master cylinder from Napa for a 72 3/4 ton 4WD

the ports sizes are different from front to rear on both the new and old one.

they are backwards, the bigger port in on the rear on my old one, and on the front on my new one.

to make it more difficult, the port sizes on different on my proportioning valve.

where do i get the correct short brake lines from master to proportioning valve?
is it possible my proportioning valve needs to be changed and matched to my master cyl?

**EDIT**

i just read down a few trends for the answer, i should have looked first, sorry!