Hi All

I am nearing completion of my trialer, now the tricky part, wiring.....not being an electrical expert, or anything else for that matter! I have put together a crude diagram of what I think I need, would appreciate anyone who knows looking over my diagram and thoughts and offer any comments.
Thanks all.

I find a well thought out diagram invaluable and worth investing some time in.

Mine will be a little different but the technique may be some help to you...

From your little diagram, a major problem exists around the starter motor wiring and the relays you have in that area.
The motor is usually energised by a solenoid; a large current relay. The wiring to that is usually direct to the battery and not through a fuse, the stall current for a good starter motor is in the hundreds of amps.
You don't need a circuit with all the bells and whistles but I would advise that you try to get hold of the diagram from say a series 2 or 3 which would tend to fit your requirements much better.

I would use a FIA battery cutout and run the alternator to the cutout switch then if the alternator shorts out when full of crap you can knock the cut out off and fix the prob.
I take it you have a starter with a soleniod on it, my trialer has a 40A fused feed to the start relay but my starter switch is in the ground side of the relay winding as is the switch for the fan relay.
The wire to the starter solenoid needs to be bigger, I think mine is 50A
Relays are four wires, you need a feed to the coil windings
Also you don't show a main power feed to the starter, this needs to come from the cutout switch.
I would put in a main relay opperated by an ign switch, this can then power up your other relays and coil etc then you can stop the engine with the switch.

Muddy Duck order some
Wire and an FIA cutout switch probably best to get some
Sort of housing I used an ip rated box but would have got an Ali one if Maplins had one in Stock at the time for all the wiring and I can shoot over and knock some wiring bits up. On the diagram I never saw an alt light you will need this for it to work. If you order your warning lights, a couple of Land Rover sidelights (for ign and the fia switch gives the alt somewhere to dump its energy without destroying itself. Also a visual aid as the resistor could come disconnected and you wouldn't know.) all the wire and an fia switch we can sort it either one or two evenings or your free or a Sat morning. Shouldn't take too long few hrs graft if we wire it and leave you to p clip it up even quicker. Will be nice to see your motor up and trialling / running!! If we can sort out a time it will cost you a single glass of orange squash and we can have your motor going!!