L34 = 350 hp
L35 = 325 hp
L78 = 375 hp
Mine is an L34(I think) or an L78(I hope)
What do I need to know to identify which I have?
It has what appears a stock high rise manifold that was painted a cheesy silver, which I repainted orange. Any other signs that don't require tearing down the engine?

l78 would have aluminum manifold....holley carb single fuel line..etc....

1968 Camaro 396 engine codes
L34 350 hp...MX - manual trans, MR - auto trans
L35 325 hp...MW - manual trans, MY - auto trans
L78 375 hp... MQ , ( MT for aluminum heads ) believe all 375 hp were manual trans but not 100 percent sure.

these codes will be the begining of VIN number on dash tag & right front pad on engine block.

I don't you can tell the difference between an L-34 and L-35 just by looking at it. You'll need numbers.