Hi from New Zealand. Unlikely to help as it's for a LJ80 but here are pages from sections 4 and 5 of a manual - Carb and Fuel related.

Making this tool may help: Alan Millyard made a bent screwdriver for adjusting carburettor screws on his motorbike - detailed video here: https://youtu.be/AZCxYTc4axY?feature=shared " In this video I show how I made a simple flexible screwdriver to adjust the mixture screws on my Honda ST1100 p...

I don't see a place to attach PDF files on this site so here is the SJ413 Manual link you can download. The ignition is covered on pages 212-222. I don't have a PDF of the SJ410 manual but I assume the methods are similar. https://drive.google.com/file/d/1NpCCX4K2rHDCclN8cZtW1q-vTDCFqh-d/view?usp=sh...

Yes, the heater resistor will be in the air flow inside the heater box. It needs to be there in the air flow as the resistor wires get very hot. The photos show all there is behind the switch is the connector to the fan unit. The plastic dash was removed about 20 years ago and trays made in the empt...

On our SJ410 the heater has been stunningly reliable, despite being under water a few times. I'll see if a photo can be arranged but surely the heater speed control is simply removed by removing the knob and then undoing the nut that holds the switch body to the dash? A SJ413 workshop manual has bee...

A few manuals attached, The SJ413 manual I have is a pdf and not a supported file type to upload here.

What model?

Is it a block heater? An electric element for pre-heating the engine coolant in the block.

Very nice bit of kit - and the high roof is interesting - haven't seen that on a these vehicles before.

DRL Daytime Running Lamp?
D/L Door Lock?
BCM Body Control Module?