Relay wiring help for LPG/petrol please

[Rovernaut]

My Disco is on LPG .there are 3 relays that control the starting of the system plus the Airod solenoid connector.
I have been trying to figure out why my starting on LPG is difficult and believe the relay thar controls ther Petrol start injection was probable cause.
The problem is I have some how mixed the wiring up. I hope some of you might be able to help. I'll run on LPG once started but when I switch to petrol the starter solenoid still stays engaged after the engine has started and is running. This doesn't happen when it's running on LPG.
I suspect that I have a short somewhere whilst it's running on petrol.

2 relays are 5 pin ( change over relays?) with the 87 'A'.
The other is a 5 pin standard relay with 2 87s.
On one relay all the terminals are used and on the other 2 only 4 terminals are used, (the centre terminal is not used)

I have a 3 pin rocker switch on the dash that is the LPG /petrol change over switch.
I believe when LPG is selected and ignition is turned to start a relay acivates the petrol injectors to enable the engine start, then deactivates and the LPG system takes over.
When petrol is selected the relays by pass LPG and allow full petrol running.

does any one have a systematic wiring diagram that could help me to correct my setup?
Any help appreciated.