From your description you have a bad master cylinder. Lack of brake pressure will only be two things - air is trapped somewhere or the master is not making the brake pressure.
I purchased mine around 2 or 3 years ago (not quite sure) - not long after Tony released them. Yes the same as Vans Auto.
Vans Auto evidently purchased the reproduction part of Tony's business.
They are worth buying. I purchased a set off Classic Industries that I on-sold and the Tony's set is...
That did used to be the spec for road car oil filters. If 21 is all you can get it should be OK.
Realistically if something is wrong and you get metal flakes the oil filter does not save the motor.
Just use what you can get.
You could try a mild acid solution for an hour or two.
I stick the screws or bolts I want to paint in to a carboard box to stand them up until they dry.
If you have a heater you could tap in to the hot water "out" of the engine.
Those sensors work better if they are in water flow - not a dead end.
A dead end can trap an air bubble and the sensor may not work very well.
I am quite sure about my calculated figures for your intake valve closing point.
I have used Wallace Racing calculators and they are good - but I have your static/dynamic numbers at a bit higher.
However this difference will not matter to most folks.
If your engine runs well and makes reasonable...