I know that; I played that game for years before the SNES came out, but the assembler supports the Ricoh 5A22 that was used in the SNES. The Ricoh 2A03 used in the NES is basically a subset of the SNES' processor.

I was commenting on the fact that since the assembler itself supports the 16-bit variants of the processor family, it couldn't be the same assembler that would have been used to build the original NES code, so the exact assembly language used might not be a precise match either.