Not a spare as such, but wouldn't be keen on going remote with a 300tdi without some form of temperature/coolant monitoring. If the engine gets hot for any reason its likely going to be stuffed. If you catch it before it gets properly hot then you've usually got options for repair.
I love the Engine Watchdog monitors as they are very simple, a non-invasive, and just work! I've got them on multiple vehicles and they have been saved me from a cooked engine a couple of times now.
Steve
1985 County - Isuzu 4bd1 with HX30W turbo, LT95, 255/85-16 KM2's
1988 120 with rust and potential
1999 300tdi 130 single cab - "stock as bro"
2003 D2a Td5 - the boss's daily drive
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