Right. Whatever you do, keep the bars as close to level as possible, in order to have surface-to-surface contact beween the bars and the L-brackets. If you life the L-brackets too much, the bars will ride on the front edge of the L-bracket, and you will quickly start wearing the bars. This will increase the friction level, creating even more wear, creating more noise and further increasing friction. It's a visious circle that will end up having so much fore-aft force on the L-brackets that the move/twist on the frame.
Ask me how I know...
thebrakeman ('70), DW ('71), DD ('99), DD ('01), DD ('05)
2004 Surveyor SV261T (UltraLite Bunkhouse Hybrid)
2006 Mercury Mountaineer V8 AWD Premier
Equal-i-zer WDH (10k), Prodigy Brake Controller