Uv layout for retopologized base mesh

hi there,

issues with workflow in production for an animation ready - human shaped model

-> base mesh maya
-> uv layout
-> mudbox
-> level 4/5 detail
-> paint texture in mudbox
-> high poly to maya
-> retopology with the new modeling toolkit

-> and now? how the hell i can transfer the old UV LAYOUT to the new base mesh created in the Retopology process?

i need this to use the texture created in mudbox for the old model