Really appreciate this thread.
I have completed the mod on my 24v HJ61.
The wiring colours are exactly the same as described in the thread.
The method is exactly the same as described in the thread.
The only difference is fitting relays with a 24v coil. I couldn't easily find high capacity 24v relays, so bought 24v 10A relays. Given 24v draws half the current of 12v, they are the equivalent of 20A relays, so I figure they will be quite adequate.
EDIT - I found the low current relays were not up to scratch and have bought proper automotive SPDT change over five pin relays. These are rated at 30A and will be much more satisfactory - ENDEDIT
I've refined the instructions to help fellow Aussies not familiar with some of the terms used. These build on the instructions at post
https://forum.ih8mud.com/showpost.php?p=4067473&postcount=51 and are aimed at folk who didn't buy relays with a ready made harness. Best to go back to posts 47 to 51 and carefully read everything they say before following my steps.
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UP Relay
Cut the Green with the yellow stripe wire.
Connect the end closest to the connector to Pin 30 on the relay.
Connect the end closest to the switch to Pin 85 on the relay.
Down Relay
Cut the Red with Yellow stripe wire. Cut this wire about 3cm along from the other cut to allow the relays to sit flatter.
Connect the end closest to the connector to Pin 30 on the relay.
Connect the end closest to the switch to Pin 85 on the relay.
Splice two wires into the Blue wire that runs between the connector and the switch. Leave this blue wire connected to both the connector and the switch. Connect Pin 87 on both relays to this blue wire. Note - Pin 87 connects to Pin 30 on the relay when the relay is not energised – i.e not turned on.
Connect the remaining pins on both relays – Pin 86 on the coil, and 87A to Ground on the door. Note: Pin 87a connects to Pin 30 when the relays coil is energised - i.e. turned on.
<<<
Hope this helps 24v Aussie users.
Tim