Both are off a Majesta and 40+40+40 pin. The 30740 being from the 93-94 and the 30500 from the 91-92. Are there other models I can exchange with? I've read the soarer ecu might be possible too.
I would swap them fine. Soarer ecu plug in and start engine but there are differences between systems. Soarer doesn't run trans temp sensor in the transmission where crown does etc.