Locally based property firm Downing wants a top-class designer to work on the 1907 waterfront building - one of the city's famous Three Graces - as part of a £20 million facelift.
Last October the AJ revealed that Donald Insall Associates was on the verge of securing planning permission for 18 luxury apartments in a new roof-level extension to the building (AJ 07.10.05).
Now the developers are searching for a practice capable of creating apartment interiors that could 'rival those in Manhattan'.
Downing director Ann Lodge said: 'The Port of Liverpool building enjoys one of the best-known locations in Europe and these apartments will be by far the most prestigious residential addresses in the city.
'We are looking for someone who can work with our team of conservation architects to produce a design that both reflects the building's status and opens it up to a new era.'