Under the bonnet, in the tool tray, I have a jack, extendable wheel nut spanner, and a modified prybar for the hubcaps. A mini socket set, and an equivalent screwdriver set. Venhill tool case which has a mixture of sockets/screw/allen fittings. That case also contains a Leatherman multitool, a 10mm/13mm spanner and a single Imperial allen key (for my rocker cover). Ratchet spanner set, and a set of three pliers in a tool roll.
Spares wise, I have three tobacco tins - they contain fuses, jubilee clips, cable ties, a selection of wire and connectors, chunk of copper pipe (for splicing hoses), a selection of nuts/bolts and washers. A small length of heater hose, some insulation tape and a spare idle jet. Full set of bulbs. Also got a box of matches - they are perfect to use as a 'rawplug' when a woodscrew has lost it's bite.
Under the seats I have oil/water (in 750ml Aluminum bottles) and an electric tyre pump, plus a couple of fire extinguishers and a can of carb cleaner. And a towel. Very important.
It may seem a bit overkill, but having run classics for many years there is nothing more frustrating that sitting on the side of the road for hours for want of something that your shed is full of! Some of mine is also specific to my car and a result of issues I've had (carb cleaner/idle jet). Idle jet got blocked on holiday and was a quick roadside fix.
