Ok, I have now replaced the booster from a donor vehicle (2nd hand). The booster looked nice and clean inside.

Unfortunately I am now experiencing some issues with bleeding.

I have bleed all 4 corners of the car, starting first with the rear right, then the rear left, then the front right and finally the front left, but even after 4-6 rounds of bleeding each corner over 3 days, I am NOT getting any firmness back in my pedal whatsoever.

The pedal goes al all the way to the floor with minimal resistance. Another weird feeling is the pedal gets a LOT easier to press about 60% of the way down its travel.

Is my master cyl poked?

Yes, I have cycled the DSC pump with INPA/ISTA and it has made no difference, the brake fluid coming out of the system is clear and without contaminants/bubbles (see photo below).

Can u send me pictures of where the hose goes ? My vacuum pump brake is left open and I want more information and pictures to were the hose should go as The previous owner Mickey moused it by the way I know I have ae70 x5 4.8

https://i.ibb.co/rM6j4WH/IMG-7096.jpg

Proper bleeding sequence is
Fill mast Cyl to top
Pressurize the master cyl to 20 PSI using what ever pressure tool you wish
Open the bleeder screw RR
bleed RR FIRST as it is the furthest away and will take the longest to bleed out.
activate the ABS module unit
while the bleeder screw is still open press the pedal three times
wait until all the bubbles stop
Close bleeder screw and move to LR

Rinse and repeat RF, LF
Note 1: RH drive applications, is the mast cyl on the right or left side? Reason: Bleed the opposite side in the rear first (LR, RR, LF, RF) some manufactures just moved the seat and all the under hood parts stayed in the same locations with the exception of the street shaft.
Note: When the master is toast it will not hold pedal pressure and the pedal will slowly sink.