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Many thanks, aelmpvw. Emmie was pipped at the post again.
There are fourteen 5-letter positions, of which three can be easily eliminated. After that, it's a matter of counting the letter frequencies. Looking for the possibility that has E in the fourth position gives the correct location. In this case, E does have a very high occurence and is doubled. Unusually, C is not at all common, but there is a rare word that starts with it.