Alarm Question

Hello! I took on a 93 Daytona 1200 last year, needed recommisioning. Mostly things are going ok, but I am at a loss as to where the hell the alarm/immobilizer would have been mounted?

It's marked as a spyball system, operated by a seperate key. I havent been able to find out much about how they work and have very little experience working with security devices.

The wiring comes up under the seat, between the battery and the fuel tank mounting bracket but there doesnt seem room to mount the box anywhere.

If anyone owns ann early Daytona 1200 they may be able to enlighten me!