You'll have to bear with the weight, no other way abut it. Unless you fabricate a custom one out of aluminum.
Just reduce the weight of the car some more to counter act the hitch.
How much have you got your weight down to? I'd assume you have ss headers, removed all the unnecessary crap from under your hood(cabin filter tray etc), removed your AC drive belt, have only a driver seat present in the car ... already
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