I haven't had any real dodgies on Datsuns, asides from an old Bluey with a cracked head that I kept going with iron tight for 3 years, but my old man and I did the cheapest engine rebuild ever on my first car - a 1966 RT40 Toyota Corona!

We had three old stuffed 2R engines lying around (which I had blown up earlier - don't believe the myth about Toyota reliability!!) and I burned a hole in the top of a piston on a 4th one. As I was strapped for cash, we pulled the engines apart and grabbed the best looking bits from each one. We even reused the meatiest looking head gasket by just putting a bit of copper spray on it. All up cost for rebuild was $3 worth of copper spray. Then engine lasted another 6 months