that, subject to subsection (d) of this section, wages surveyed be those paid by private employers in the wage area for similar work performed by regular full-time employees, except that, for prevailing rate employees under paragraphs (B) and (C) of
section 5342(a)(2) of this title, the wages surveyed shall be those paid by private employers to full-time employees in a representative number of retail, wholesale, service, and recreational establishments similar to those in which such prevailing rate employees are employed;