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!

[THE BOSS]

i give up, where can i find the correct lines form my master to prop valve??

do i need to get a proprotioning valve also? are they differnt from 2WD to 4WD?

[john]

You will need 3/4 ton lines. they hook up opposite 1/2 ton lines. Front to rear and rear to front.

[THE BOSS]

who has them, where can i buy them?

Thanks!

[SS Tim]

Inline Tube has areproduction prop valve and kit. it does not state however if it is 1/2 specific or if they offer a 3/4 set as well. Since they make pretty much any tube you want, a phone call should fix everything well with a cc too.

http://inlinetube.com/Prop%20Valves/VCT103.htm

[THE BOSS]

i have to sent them there, they dont have a pettern for my app, but they can do it.

Thanks You!!

[THE BOSS]

i called them that day, the guy on the phone said they dont have the pattern to make them?

i looked later on there web site it showed a picture of a complete set.

it showed the 2 that sure looked like the ones i needed, so i ordered the complete line kit online for $155

they do have the correct lines and now I do too
(along with a bunch i dont need as of now)

Thanks for the help.