Circle track guys have been using these things for years, rally drivers too. They are called steering quickeners. Howe also makes them... they are in the Summit catalog. They make them in different ratios.
The power steering in most all mopars has always seemed to be overboosted. A larger pulley on the pump will help some. The police car firm feel chuck is slightly better than the standard unit. Using the longer "fast ratio" pitman and idler arms will help too. Having your unit rebuilt to give more effort and feel is probably the single most effective move you can make though.