Just want to know What be better to do on my 04 gt cams and heads or supercharger like kenne bell
+1 i love a cam in any car lol.Supercharger will be more expensive but you'll see over 2x the gains. But then your engine will be close to maximum operating parameters and could lead to early engine failure.
Heads/cams would gain over 60rwhp pretty easy after retune, and add in a higher-flowing intake manifold and you got just under 90rwhp probably with a great tune. But that's only iff you go really aggressive with the new parts and tune.
Personally I'd do heads/cam first... I LOVE the lope of an aggressive cam.