The most obvious solution is to get it inside a garage somewhere it can warm up enough to start on its own.

Other questions in my mind are the condition of the glow plug system and the valve adjustment. I just checked the weather in Fort Wayne (I assume that's your area or reasonably close to it) and it's warmer there than it is here. My junk is high-mileage but has good plugs and current valve adjustment and has been starting without having to plug in.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.