If I get a PAL-region game, and try to play it on a NSTC NES, will it work without modifications?
Top loader NES consoles don't have the 10NES lockout chips installed, so they should work out of the box. On a front loader, you'll have to cut a pin out of the chip to make it work region free.How weird, I've literally just tried this.
I'm UK based, and using an American toploader, with an AV mod. I tried several PAL titles on it, and they all fit, and worked albeit with faster music. (higher pitch too)
If it's a normal NES, I'm not so sure. But it would have the same outcome if they fit. (faster music)