it is a concern what you mention about the insurance... i never buy insurance aside from what is mandatory but i do consider myself a very good driver, very careful on the street and have never been in an accident - avoided many.
*edit* in fact, none of my cars have ever been roadworthy, always random stuff welded to it with random mismatched suspension riding 40mil off the road.
the pic doesnt show properly where i have welded it but at the front of the brace is some 65x3 flat bar folded over the skirt and welded all around. its also welded to both door hinges, the underside of the bottom of the brace and several other places along the brace. i also used the highest tensile weld metal i could get, very strong and good peno stuff.
i personally felt that this was more than adequate but if you think there are other places i should weld please let me know.