where does the residual pressure valves live? I had discs before I went manual disc is this something I should have added?
There is a residual check valve on the port for the rear drum brakes. It is behind the seat. To access it you would use a screw to remove the seat. It will have a rubber check valve and a spring. This is only used on the drum side. You do not need this for disc and would make the calipers drag. Only time you have a residual valve on disc is if the master cylinder is mounted below the caliper which you do not have.
Now there is also a proportioning valve which is part of the metering block and is plumbed into the line to the rear brakes this is used to keep the rear brakes from locking up in a hard stop. If your setup was the stock disc/drum from the factory your stock one is fine. If you have different rear brakes you can get an adjustable proportioning valve, but it does not sound like this is your problem.
I would verify that the master cylinder is a disc/drum type and has the residual check valve on the drum side. If it does not you will have excessive pedal travel. That all said the manual setup will have more travel since the manual brake pedal has more leverage and the master is a smaller bore. This is required to still be able to generate enough braking force without assist. If you go to a bigger bore master cylinder your pedal travel will be less, but the effort will go up.
Considering you went from a Hydraboost to manual brakes I am not surprised you are not happy, as is said "there is no free lunch". The old manual Ford disc/drum setup works, but will not match what you had. If you want to get rid of the hydroboost next best would be the factory vacuum booster and 1" master cylinder setup. You can add a vacuum tank and there are OE vacuum pumps that can also keep the vacuum up if you have low vacuum because of a long duration cam. Other option is electric, but that seems to still be an expensive option, have not heard of any DIY setups yet.
