Spark and chop shop
There are a couple of things I have done in recent years that could help both of you.
It is possible to put a Gemini booster and a Falcon master cylinder up under the dash of a model A with the cylinder facing straight back towards the driver. I have done it using a modified Holden Shuttle van pedal assembly. There is not a lot of room but it fits.
This photo shows the pedal and cylinder/booster in my current car. The pedal is a very much modified one from a VP Commodore and the booster is a stock VP with a matching 1 inch VP cylinder. I have mounted the booster further back and a little higher than usual so it does not hang down below the chassis. It does stick up above floor level but it is behind the seat and easy to get at. The cylinder is also higher than all four calipers. The shaft connecting the two is made from a length of pipe with a pedal to booster rod from another VP welded into the front end of it. My engineer has inspected and passed everything.
Although the engineer says it is not necessary, I still intend putting some kind of rubber or spring loaded support on the shaft to stop any vibration.
This is a good way of putting a full size booster with its own cylinder under the floor without running into clearance problems.
It may not work on all chassis though because the top of this X member is slightly above floor level allowing the booster to go higher but it is worth checking out. It could be useful in other applications