1977 Toyota Celica GT engine stalling

Hi, I have a 1977 Toyota Celica with just under 4,000 original miles. The
engine wants to stall when I first press down on the gas pedal, just the first
inch of pedal travel, if I can press the pedal fast enough to pass that zone
quickly, the engine RPM’s will not drop and I can accelerate normally.
The second way it will stall out on me is if I’m slowing down as I approach a
stop sign or red light, I will watch the speedometer and the tach, RPM’s are
normal as I’m slowing down all the way till my speedometer hits 0-1 mph,
then the tach instantly drops to 100- 300 RPM and it will quickly stall. This
happens when the engine is cold, and also when the engine is running at
normal operating temperatures.
The stalling is an intermittent problem, the engine will try to stall out at a red
light, and 3 blocks later its running perfectly. There is no predicting when it
will strike! The car was stored for decades, I have already replaced the
plugs, wires, cap, and rotor, plus I have replaced the clutch and brake fluid
master cylinders and flushed all the old brake fluid. Other than the stalling, it
runs like a champ and is a joy to drive. If anyone can help me out it would be
much appreciated!