Cisco Switching/Routing :: Setting Up Nexus 5000(s) For Inband Management?

we do not have an out-of-band management network and setting one up at this point is not being planned.  We are mainly a swtiched environment and the only devices that are using L3 are the core switch for WAN purposes and the lab because it is mimicking the production environment.  I have two Nexus switches that are sitting on the other side of a 3750 switch which is currently acting as a L3 device because this is a pre-production environment for a new project.  We had an issue with management of the devices before but our workaround was to put them on the management vlan direcltly off of the core, allowing only management traffic to pass by means of mgmt0 on each device.  The problem I'm having now is that I've now setup the mgmt0 interfaces on both for the keepalive link for vpc only (vpc traffic is going accross 2x10gb connections and the link to the 3750 is 1gb each trunked) and have lost my ability to use the mgmt0 connections for management. How to connect my management connection through either the 3750 or directly off the core switch (as that's what will happen once it's put into production)