ford f150 truck

hello there guys I have a 97 ford f150 4.2L engine with over 300,000 miles and the engine just seized the other day and I been looking around to get info if its worth getting rebuilt or just getting a new engine or just scraping it but I also find out something bout the early f150 and wondering if that could be the issue or wat could cause it to seized but b4 it seized it got 2 codes which were p0303 and p0174 so if anyone can keep me with any info I would truly appreciate that
Thanx Derrick

Purplehazeir

The P0303 is a misfire. P0174 system too lean. The engine seizure can be from any number of causes. I would pull the plugs and see if you can get the crank to spin with a wrench on the flywheel. If not...then you probably have seized the crank or busted a rod and famed a piston. Probably going to be cheaper to get a crate motor, rather than pulling the current one and having it rebuilt.