And the reshuffle also sees ex-Jaguar chief Jonathan Browning brought back into the General Motors fold.
The former Ford man will assume Reilly's previous responsibilities at GM Europe as vice-president of sales, marketing and aftersales.
Reilly has been tasked to head the Daewoo 'transition team' in South Korea by GM global chief Rick Wagoner and after the conclusion of the due diligence period, will assume the title of president and CEO of the new company.
Browning resigned as managing director of Jaguar Cars in the wake of Jac Nasser's departure from parent company Ford. He rejoins GM Europe after departing to join Jaguar in 1997 and will be tasked to return GM's European operations to profit under the manufacturer's 'Olympia' programme.
And, as part of its Olympia programme, Opel has announced plans to 'significantly expand' its used-car activities.
Andrej Barcak, currently management board member responsible for sales, marketing and customer care, in charge of developing the project that GM Europe said will 'eventually result in an independent Opel/Vauxhall used-car brand'.
Mark Fields continues as president of Mazda.