Raising the rear end

i had 3" shackles on the back of my high school one and no air in the air shocks, held it up above my 10 inch tires. Couple of fatties in the back would cause it to rub so I put a few PSI in the shocks to keep it up. BAD over bumps though, shocks would hyper extend and try and pull the shock mounts out of the car...