I'm not really getting how the downs work/fit in...
With one exception each down clue has an extra letter provided through wordplay to form the entry...
2d Ed's visor dead centre in basinet cupped in hands (7) NUMBR??
9d First person in middle of exploits to find islands (5) ?C?T? i/me for 1st person ? acts /exploits??
27d Married female relative embracing independent editor 97) ?UN????