Hi, I have both the necessary part and the extra part for the Highwayman car. Now, when i want to go to Smitty in The Den, I can't find him anywhere near his garage or in his little hut.. where can i find him? Has he moved? Or did i encounter a bug?

I don't know if it matters but:
When i enter the town, i always have to fight with the guards from the bar/casino on the east side (in the west side of the town). I once tried pickpocketing a guard but got caught and have been hostle with them ever since.

Thanks in advance, Adrian.

Probably dead somewhere. Or sometimes they flee when combat starts, check in the far corners of the map or around walls that you view might be blocked.