The Radio 2 DJ was announced as Jeremy Clarkson’s replacement on the BBC Two motoring show last month, after the long-standing presenter was fired for punching a producer.
His co-hosts Richard Hammond and James May also quit the show in the wake of the debacle, leaving Chris to find a new presenting team.
Speaking about the hunt, he told Top Gear magazine: "It's nearly in place. We're so very close. There have been 34 presenters before me, so it's a bit like ‘Doctor Who’ – that's one way of looking at it."
“This is, without doubt, the most challenging thing I have ever done in my career. When I took over [previous Radio 2 host Terry Wogan's] show, people kept saying I had "big shoes to fill", and they're saying it again now,” he continued.
“I don't mean they're wrong or they're right, it's just such a predictable thing to say – and, by the way, Jeremy is very tall, so they're even bigger shoes.”
Chris also let fans in on what to expect from the format of the revamped show.
"Nothing has to [stay the same], but some things will,” he said.
"I can't tell you what precisely. But it would be silly to throw the baby out with the bath water."
Formula 1 presenter Suzi Perry previously confessed she had been approached by producers to join the show.
Speaking on ‘This Morning’, she said: “You know what it's like when you work for a channel and you have conversations… but we don’t know what’s going to happen with that show.
“You know what it's like when you work for a channel and you have conversations… but we don’t know what’s going to happen with that show.”
Jodie Kidd and Clare Balding are also among the female presenters to have been linked to a ‘Top Gear’ presenting role.