It would just be a bar you could attach a 4 or 5 point harness to. Harness straps are supposed to be attached behind the seat at or near shoulder level in order to function properly. A full roll cage would probably need to be welded in and custom made for the car/driver, so its not really feasible. The bar would give you the option of using a harness for auto-x or on a track to hold you in the seat better. Harnesses are not street legal unless they come like that from the factory, because they modify the vehicles safety equipment. To remove it, all you would have to do is remove the 4 top bolts, then remove the 2 bolts for the support struts, take the bar out, then re-install the bolts. Pretty simple, and it shouldn't take more than 5 minutes