The residual pressure valve needs to be removed as previously noted. You should install an in-line valve for the real brakes.
This will keep you from having to pump up the rear brakes every time you stop.

I believe I bought the calipers, mount plates and discs you sold a while back.
I did not use the discs or calipers.
If interested let me know, we can work something out.

Tracy,
five 6 2 544 ten ten

As the discs and hubs, with wheel bearings, are standard Volvo you don't have much choice. Luckily they are now available new at a much lower price than the originals that had to be refurbished by shrinking on new discs. The new ones are all in one piece for about half the price. I put some on my Amazon and they are good. If you have managed to do a conversion that uses the later seperate discs please let us have the details.

I did the transplant (from an 1800) many years ago. I didnt touch the rear drum brakes other than to install a proportioning valve ( think I got it from summit) and removed the check valve in the front of the master cyl. It feels like I get adequate braking without power assist. Wish I had figured out a way to split system front and back and retrofit a tandem MC but gave up on that along the way.
Dean