How to produce a Hash160 bitcoin address?
The address is already a hash, together with a 4-byte checksum and a version byte.  To get from an address to a hash160, you don't have to compute sha256 or ripemd160 of anything.  You just have to decode it from base58 back to hex, and discard the unwanted junk.

If you take mvm74FACaagz94rjWbNmW2EmhJdmEGcxpa and base58 decode, you get

 6FA73706385FFFBF18855F2AEE2A6168F29DBB597EF59C240B
 VVxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxSSSSSSSS


The first byte (6F) is the version byte; discard it.  The last 4 bytes are the checksum; discard it.  The remaining 20 bytes are the hash160 of the public key corresponding to the address.