69 gmc to 72 disc
 

I’m finishing up a disc upgrade to my 69 gmc with hydroboste. I got two questions that I need some guidance:

1. Do I need a new porporting for the disc brakes or can I use the existing?
1.a. If I need a new porporting do I need to run 2 new front lines as the old hydroboste had one line out of the porporting to both front from a Y junction.

2. Inner tie rod isn’t working for 72 spindle but ordered year specific from rock auto. How tall should the shaft and thread be on the inner?

Any help or advice is greatly appreciated.

Re: 69 gmc to 72 disc
 

For me the old combination drum/drum caused problems.
I bought a disc/drum prop valve from inlinetube.com
They have one just for this retrofit 69-70 drums to 71-72 disc.
I also bought new lines from them. Perfect fit and reasonable cost.
Heck stainless lines where only another $25 for the entire truck over steel.
I later added rear disc and was able to keep old prop valve. Just had to remove the metering rod (not sure exact name of it)

Re: 69 gmc to 72 disc
 

Update
1. Bought porporting valve from speedway and got reducers to fit as well as plugged one front brake line since both were running to one. In the future hope to run separate brake lines. Moving in a few weeks no time.

Spindles issue..... I ordered the wrong outer tie rods. Reordered and everything works.