Rev limiters in these older ECU's are of two types. Some ECU's have one, some the other.

One type is minimum time between two flywheel teeth.
That one works by dividing a number related to the microprocessors frequency by a 16 bit float which in these is X/2^Y if X is high byte and Y is low byte.
Other one is just a 16 bit integer, which is again time between flywheel teeth and is the microprocessors frequency divided by the value.

In both cases, if you want to have higher RPM you must lower the value.
It would help to know what clock speed the cpu is running at (look for the xtal on the board).
In that location A355 and A356 look more likely, but to find out what it is exactly you can either try changing it with the emulator or disassemble the binary.

Yes, the 16 bit float is X*2^Y if Y is <128 and X/2^(FF-Y) if Y is >= 128. It is how floats are represented on these old ECU's.

The factor is never the same because the factor depends on the clock speed of the processor as well as in the first implementation on the count of the teeth on the flywheel.

I have no problem finding the rev limiter in this, takes me 10 minutes... but that is because I can disassemble the file and I know how the rev limiting works in these old ECU's.
Too bad about your Ostrich... time to get a new one. I had three at some point, now two