A-arms are a good upgrade, but you wouldn't want to attach them to the stock bulkheads,the bulkheadsshould be first. Start by building a strong 'core', then work your way out. I have aluminum bulks, rpm a-arms with the true track, lunsford hinge pins,aluminum skids, rpm bumper, shock towers and some other goodies. I'm eventually going to get aluminum chassis braces, but the stockers are still ok. I left the stock axle carriers up front for a planned weak link when I hit stuff.