Ha ha, I don't think anyone would know what a slide rule is nowadays Dave, my old man had one and tried to teach me how to use it but I wasn't that interested, and he wasn't that patient. Yep I should have kept my XR, XY, XA, XB, XC, LC GTR Torana, HG Monaro, Mazda RX2 Coupe, etc, but most of them would have rusted into the ground if I'd stored them outdoors, and I've never had garage space for a car.
My dad's 1984 XF wagon is covered in an inch of dust in the garage at Mum's place and Ma want's me to wash it, but I explained that the only rust it has in it now is because before he died, I thought I'd do Dad a favour and put it thru the car wash then parked it back in the shed when it was wet.
God knows what I'm gonna do with it when Ma leaps off her mortal coil, like all cars of the 60's-80's, as soon as it's parked out in the rain it'll rust itself into oblivion.