The only spares I carry are a few bulbs & fuses. Obviously also oil, water, antifreeze, and screenwash. I have a torch but that's mainly used for checking the oil in the dark and also a towrope & jump leads which are hardly ever used. There's a few tools, and some spare lights / reflector units & housings but they're in the boot more for storage reasons rather than necessity! I use the standard jack, and other than when the nearside rear outer sill partially collapsed through rust (since replaced - the actual jacking slot / lug was fine), it has never given problems.
Interesting to read your overheating story - I've also heard that these engines can take that sort of punishment without complaint.
http://x-files.serveftp.com/paulhark...ture.sized.jpg
1967 Amazon 122S B20 o/d Estate, 1961 A-H Sprite Mk2 948cc