For road trips in any of my/our cars, I've always carried my auto tool kit (full kit SAE & Metric), plus spare fan/accsy belts, spare set of spark plugs, misc fuses & screws/nuts/washers, elec. tester, compression tester, etc., & a smallish travel battery charger + jumper cables - although now I just carry an LI battery starter/charger instead (I-start from GoWesty, but they've changed brands).
PS - add proper jack, wheel chocks, coveralls & gloves, plus warning triangles &/or flares.
PSS - for you in OH, if you drive in winter, a bag of sand &/or snow pellets to help out of an icy situation.
I'm originally from Pittsburgh, & have driven in snow a lot even in SoCal (I used to go skiing with my 914 too), so I know!
Survival food/water packs 1/per seat, blanket(s) & sweatshirts/jackets, bright safety vest, & a cell phone are other obvious items.
Those LI starters are smaller than the cables & don't require another car to jump, & I helped 3 cars start after charging both our cells the night before, at one of our vintage trailer rallies (classic cars with old batteries too). Cna't say enough about how handy they are!
Tom
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