I had an offer to buy my truck from a neighbor so he could soup up the engine. I don’t know much about it, but he said you could add a huge nitros system to the engine in about 20 minutes, double the horsepower and the truck would not notice the extra stress.
I sold the truck a year later because I was tired of putting brakes on it and the master cylinder had seen better days. I was also promoted and got a company truck (a newer F150, 4.6 V-8).
When I advertised for the truck, I did get a call from two people who just wanted the motor. They didn’t even talk about the price. I asked why they just didn’t buy the truck and take the engine out themselves. Still baffles me.
If you check the recycler site car-part.com you will find you can find a bunch of 4.6L ford engines with less than 100,000 miles for around $500.
They run for over 300,000 so they are almost never overhauled. (That is $3000)