Some friends of mine (Thanks Tim and Bruce) were dismantling a 30kVA UPS and scrounged a few parts for me.
Circuit Breakers. The large unit is rated at 250VDC, but has a micro switch that I will use to release the contactors if triggered. This should perform adequately with only a few milliseconds of 300+ volts.
The 50 amp units will be used on my 2 x 25A 12 volt supplies.
16mm2 cable (overkill but will work very well)
I bought 13 x 48 volt / 2.5 amp SLA chargers from e-Crazyman (eBay)
They are fairly large, but quite light. They are fan cooled and are 2 stage.
I also received an RS232 to RS485 adapter, also from ebay, so I can 'talk' to the Danfoss 6042 drive when it arrives on Monday.
Things are progressing, but there is a long way to go.
I am amping to finally get a vehicle.