The eight-year-old grey was previously beaten comprehensively by Planet Of Sound over fences in the William Hill Gold Cup on his seasonal debut at Exeter.
"Nacarat's on target but the one thing we learned is that we won't run him on an undulating course again," said George.
"His forte will be three miles on a flat track, going right-handed - so we're looking forward to Kempton."
Meanwhile, connections of Carruthers insist they would have gone close to winning the Hennessy Gold Cup had the six-year-old not missed last Saturday's epic chase with a throat infection.
Trainer Mark Bradstock's wife, Sarah, said: "I was dreaming of an easy victory. We thought we would have beaten the runner-up What A Friend and he would have given Denman a run for his money.
"Carruthers is still on the easy list. You can't take chances when you are a small yard and he had a low-grade virus.
"But all being well, the plan is to run in a valuable race at Ascot on 19 December [the 3m Sodexo Prestige Silver Cup Handicap Chase]."