I've managed to solve nearly all the bottom half of this, but the top half is proving elusive.
Solutions to the following might kick-start my sagging grey cells :
1A - Manage to keep down an American roll and glass of beer contained (9)
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6A - Protective cover, one Fortune had over temple in Rome (7)
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&
15A - Need no guidance to cope with small pigs, including one very small creature (3, 6)
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I also have two interconnected clues in the lower half giving me grief, viz :
49D - Discuss time to introduce English book (6)
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&
55A - Persisting with an attempt to perform choral work abandoned by Society (7)
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Any assistance gratefully received