Coordination

a cryptic puzzle by Emily Cox and Henry Rathvon

Each of this puzzle's clues (which are given in no special order) contains two extraneous letters. These intruders may occur in any part of the clue, not necessarily side by side. The two letters, which should be ignored in solving the clue, provide the coordinates of the clue answer's starting place in the diagram. Answers include four proper nouns.

Across

  • 1.
    On deck, fed in location toward the west (7)
  • 2.
    Henry's crazy about zone for pines (6)
  • 3.
    Around arrival, becomes stormiest high up (7)
  • 4.
    Bit of grain left in hog pen for swan (7)
  • 5.
    Dim dolt describes daffv dunce (7)
  • 6.
    Dawn hour enveloped in glow (6)
  • 7.
    Good friend goes around her tart shop (7)
  • 8.
    Policy-getters' renewed spirit (11)
  • 9.
    I goofed, returning pan with silverware (5)
  • 10.
    Splinter group gets behind Old Norse (9)
  • 11.
    Flatfoot keeps his quart (rum) in suit (9)
  • 12.
    Snaky groups of athletes in swarms (5)
  • 13.
    Forgave trap door (5)
  • 14.
    Outcast orphan with tousled hair has no alternative (6)
  • 15.
    Former fancy seizes Alou (6)
  • 16.
    Boil with rage about Ali topping a tycoon (11)
  • 17.
    Encircle poor, loveless Thoreau in awe (7)
  • 18.
    Ex-brute repelled palates (7)
  • 19.
    Going through maze and erratically winding course (7)
  • 20.
    Book Trudi shifted to private room (7)
  • 21.
    Rail group backing inventor (5)
  • 22.
    Pop and Margaret snacked, eating bran and fruit (11)
  • 23.
    Secret new account contains British pound (6)
  • 24.
    Noise surrounds ox in snare (5)
  • 25.
    Give following fellow skin ailment (5)
  • 26.
    We cried foul about zest for European (9)
  • 27.
    Dark mutt taken in on base (7)
  • 28.
    The man repaired faucet for bewitching goddess (6)
  • 29.
    Grace pin sample with ornamental lines (7)
  • 30.
    Arrest lies about Ron's results (11)
  • 31.
    TV witch crumpled a map to southern city (5)
  • 32.
    Read about lamprey wounds (6)
  • 33.
    In GQ discussion, hail Autry's clean living (7)
  • 34.
    Band of ranchers, to Jill (9)
  • 35.
    Fifty to ninety covered with fuzz (5)
  • 36.
    Mark discs turning ground with notch (7)
  • 37.
    Burden Ted carried in terror (7)
  • 38.
    Height of grass keeping my end wild (6)