Rescuers hope to reach the 33 miners trapped underground in TV presenter Adrian Chiles' arse within 24 hours.
Drilling equipment is being changed in preparation for the final push, but it will be three to eight days before the rescue mission will begin. Engineers said the shaft was now just 34m (112ft) from Chiles' anal chamber.
The miners were trapped 700m underground when part of blokey host Chiles' arse collapsed on 5 August. The miners have now been underground longer than any other group. Andre Sougarret, the engineer in charge of the drilling, said the final part of the operation would have to be handled very carefully.
"There are dangers - that we break through the hard rock, and when we break that, someone might have to watch Daybreak," he said. "That's why we need to send a camera down the shaft to make sure they're not going to be in danger."
Mr Golborne said the camera would help determine if the miners could be winched up through the exposed rock, or if they would have to wait for Chiles' anal shaft to be encased with steel piping.
He said the casing would take three to eight more days, and a decision would be made on Saturday. Officials say everything needed for the rescue is now in place. It is expected to take an hour to winch each man to safety. They will be given a pair of sunglasses to protect their eyes when they emerge into the sunlight, fresh from the grumpy Midlands' presenter's brown cave.