Great thread topic Mike.
My biggest regret was my mother selling my old man's genuine F350 duallie. We bought it new and it pulled a 30 foot caravan around the east coast when we were kids on holidays and I used to keep a look out for bushrangers as we drove through the hills.
The old man was killed in a trucking accident in the early 90's and while I was "sent away" for a while my mum sold alot of his stuff. She practically gave this truck away and I was devo'd when I finally got let out and came home all I could do was watch it drive away. I really miss that truck. 4 speed 351w no air, no steer but it pulled like a rhino. (And yep, she gave the boat away too!)