Following on to thisthread. I have found out that it is not possible to bypass the hiss system on the 954.
I have talked to these guys at track electronics..link..who can modify your existing loom and change the ecu for about £260,which seems resonable as hiss systems cost around £500.

If anybody knows any different and the system can be bypassed,please let me know,,thanks

[Edited on 10/8/06 by grahamgg]