I have got lumbered with sorting a gas system for a family member

They have just bought the car and the history is unknown

It didn’t run on petrol and ran RS on gas

Plugs and a lead helped.

The cold air intake that had been blown to pieces has been replaced with 75mm PVC

I have replaced the fuel pump after a few checks and it now runs on petrol.

It has a PEEL control unit with 4 wires and a green led on the top
From left looking at the unit it has
Bck = ground
Bl appears to be solenoids
Yl ?
2xRd 1 I believe goes to the idle speed control and the other being 12v supply
with a MGA converter and it’s a closed system.

Now the issue is and being old school and never worked on this type of system before and it may just be the way it is, but to me seems wrong.

The petrol/gas switch on the dash only shuts the injectors down when in the Gas position and not in the centre position.

This means you cant shut it off while switching between fuels causing the engine to flood during change over in either direction.

I have found a relay under the dash that is wired into the gas wiring.

Now if this isn’t correct that it doesn’t shut down in the off position where do I start looking?
Has anyone got a wiring diagram for this system or similar ?
Thanks for looking

Some more info after getting under dash I have found a "Leonardo feedback system" cable tied to the car wiring, but cant read a modle # and it doesnt look like the 175, its about 1997 vintage

Some times it easier/better result if you just gut all the LPG wiring and FB controller out and start again with new gear.

A system that old may have had any number of repairs made making tracing and further repair harder then it needs to be.