Front brake conversion

Welcome to 2CarPros.

Was the master cylinder replaced? If the pedal is going to the floor (boost or no boost) the is most likely the cause. Take a look through this link.

Also, I did this same conversion on a 70 lemans a few years ago. I had to replace the booster, master cylinder, and so on.

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

I noted you are a mechanic, so I assume you checked for leaks and confirmed the rear brakes (if still drum) are properly adjusted.

Let me know.
Joe

Have you tried adjusting the push rod between the master cylinder and the brake booster?

The rule of thumb. (Basically, winging it)

The longer you make the rod (to a certain point) the better your pedal gets.

If you get it too long, your brakes will start applying and they will drag. I always put the Jeeps on four jack stands so that I can crank them up and see if I can still spin the wheels with my hand.

If you get the rod too short, your pedal will get spongy or drop off to nothing.

For me, it's a trial and error thing, it may take me five or six master cylinder removals and installs to get it right. Patience is a good attribute to have.

Let us know how it goes.

The Medic

Let us know what happens.

Joe

Sounds like a plan.

Joe