I'm converting front drums to disc brakes do i need to replace the proportioning valve

 

Yes. You do not have a proportioning valve now. You have a distribution block. You should go ahead and mount the proportioning valve on the top of the frame in case you decide to install headers one day if you don't have them already.

 

Thanks for the information i do have headers so ill mount it on top of the frame..now i eliminate the distribution block right

 

If you are using the combination valve, as used on the 1971-up cars, this combines the functions of the proportioning valve and the distribution block into one item and thus replaces the original distribution block. If you are using an aftermarket in-line prop valve only, the distribution block remains. Either way works - your call on how to do it.

Combo valve (replaces distribution block) (note this brass one is aftermarket, factory ones were cast iron):



In-line proportioning valve (requires distribution block):

 

In 69 they used a hold off valve next to the MC and the non-proportioning distribution block on the frame. Pretty sure 68 was the same. The combo block does the same function with less parts but don't know if being more factory correct is important to you.

The MC also had bleeders that were not on the later cars.

 

1967-1970 disc brake cars all used a similar external metering valve. Repros are available, though the brass combo valve is a less expensive and better alternative, as it won't rust internally.

 

I have the brass aftermarket valve it came with the kit I bought.


this is all new to me is it easy to change out the master cylinder and brake booster and proportioning valve?