Bypassing immobiliser in a 1999 Subaru Forester

I have two paddock/farm vehicles. One is a 1998 Forester (black), auto, EJ20, no ignition immobiliser. The other is a 1999 Forester (green), manual, lo-range, immobiliser. Neither came with a FOB or an ignition key. My aim was to not spend a single cent on getting both running.
I dodgied up the black auto, and it runs beaut. Cut off the ignition lock, put in a few ignition switches and its fine.
I really want to get the Green manual, with low range, running. However, with the immobiliser it is difficult. Surely there is a method of bypassing the immobiliser? Even if I have to open up the computer and solder in a wire from the security chip to another main chip(?)
I have swapped computers with no avail – I thought that the non-immobiliser computer from the running auto into the green manual, should have worked.
With either computer, the manual turns over fine, spits out appropriate fuel, but of course, no spark from the coil pack.
Found on a russian website where someone has the circuit of the immobiliser/sensor unit, but it is all drawn and handwritten in russian. Trying to decipher what it is is too hard!

Anyone have any experience?
Cheers. Dave.