Each defendant played a different role in the plot. Lorry driver Brian Mulcahay was the inside man.
Mulcahay, 46, of Grosvenor Road, Westcliff-on-Sea, Chatwood, of Sawyers Grove, and Stanley Rose, 75, of Iver, Pilgrims Hatch, both of Brentwood, and David Gale, 55, of Hansells Mead, Harlow, and Gary Cummings, 51, of Anne Way, Ilford, all Essex, pleaded guilty.
John Corley, 53, of Tankerton Road, Whitstable, Kent, was found guilty after a trial.
A seventh man, Matthew Middleton, 42, of Crows Road, Epping, Essex, also pleaded guilty and will be sentenced at a later date.
The Faiers sisters had been due to give evidence at Corley's trial but were not called.