I found an old post about this so I thought I'd throw out a new one.
It's easier to use than others I've tried but can still be a bit of a headache. I've found models of Blazers ,trucks and Burbs that you can download and then modify as well as online tutorials.
Heres a roof rack I did (not completed) and stuck it on a burb model.

It's easier to use than others I've tried but can still be a bit of a headache. I've found models of Blazers ,trucks and Burbs that you can download and then modify as well as online tutorials.
Heres a roof rack I did (not completed) and stuck it on a burb model.