Typically the ECU's were all the same part, but certain aspects of the programming was switched on or off to suit particular vehicles.
Likely the auto one is only a little different as there is no ECU electrical connection to the trans itself .. just the speed sensor.
In theory T5 suite could easily 'fix this... IF you find it's a problem
Real problem is those ecu's are old and their ancient flash memory chips may not accept reflashing, in which case the ecu would either need fresh flash chips fitted or throwing away

 

Nooooooo...

1991 9000's are Bosch LH-Jetronic

Not Trionic, therefore no T5 Suite. And No re-flashing.

Interesting Info

 

what is your reasoning for changing your lh computer out?

Saab 900 & 9000 Bosch LH-Jetronic components
complete list of lh computers and applications.

if your intention is to replace broken one stick with the stock numbers. if its for a trans swap stick with your 5 speed ecu. if you are looking for a power bump options are red box ecu's, swedish dynamics or g6 chips. last option is to convert to t5 or to an aftermarket engine management system.

 

Interesting Info[/QUOTE]

haha oops didnt see that