Dyno'ed My 360..it's a pig..what next?

I'd start over with a used 96-2000 5.9 magnum motor- 240hp rated stock..

5.9 magnum long block
Serp belt under drive pulley
Carb intake
Mopar roller cam/springs for cam
Good headers
Summit 2.5" X pipe
Your choice mufflers
Tail pipes or dumps
Non stock stall converter for the A518 - this will help HEEPS
4.10 gears - you'd be around 2,750- 2,900rpm cruising at 70mph - don't need a high gear with the OD.. I had 4.30's in my old 5 speed Mustang - cruised 75mph @ 3,000rpm