The pair met in the most recent series of the reality show on Channel 5 earlier this year, and struck up a romance during their stay in the house.
Mckray revealed that he proposed to Cliffe during a ride on the Wheel of Manchester last week, which he described as the "best day of [his] life".
He told New: "It was hard, because we're always together. I snuck off with her mate. There were millions of rings, but as soon as I seen it, I was like, 'That's the one!'
"I rang around trying to get a hot-air balloon but it's seasonal. And a helicopter ride meant going 45 minutes out of Manchester and I knew she'd be on to us. So I booked the VIP box on the Manchester wheel with champagne."
Cliffe explained: "It's all I've ever wanted. I said the next person I want to make love to I want to marry. That's the way I feel now. I just want to settle down. Everyone wants love, don't they, and we've got something really special."
Mckray - who has been engaged before - added: "I can honestly say I've never felt like this about anybody. I'm not saying when I was engaged before I wasn't prepared to get married, but it's totally different."
The Geordie gym instructor finished as runner-up on the series, and swiftly declared his love for Cliffe.
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