puzzle

 ACROSS

  1 Work to clean

  6 Shoot an air ball, say

 10 Letters on a Coppertone bottle

 13 "Ah, OK"

 15 ___ fresca (fruit drink)

 16 Vietnamese soup

 17 Its Double variety has 4 patties (Note this answer's last 2 letters + ...)

 18 Ribbed fabric (... this one's first 4)

 20 Rainbow's shape

 21 Gas additive brand

 22 Evaluate on Yelp

 23 Advocate such as Lady Gaga or Madonna (Last 3 letters + ...)

 27 John Deere product (... first 5)

 29 Train that stops in Baltimore

 30 Book before Jeremiah

 32 "___ Loves You" (Beatles hit)

 33 Gas holder

 35 One can do no wrong

 38 Nuisance

 40 Rolls-___

 42 Name that anagrams to "Oman"

 44 9 to 5, e.g

 46 Ritzy

 48 Awaiting scheduling: Abbr.

 49 Heavy club

 51 "Let's do this!"

 53 Horn of Africa nation (Last 4 letters + ...)

 56 Tropical cyclone (... first 2)

 58 Waithe of "Ready Player One"

 59 Key under Z, maybe

 61 Employ

 62 Formal apology (Last 2 letters + ...)

 64 Diagnostic med. image (... first 2)

 68 IRS identifier

 69 Rather close

 70 Stay on, as a schedule

 71 Souvenir shop shirt

 72 Singer Guthrie

 73 Less frequent

DOWN

  1 Cry and cry

  2 Tai ___

  3 Manipulate illegally

  4 P.O. box filler

  5 It isn't ursine or feline, surprisingly

  6 Computers that run Safari

  7 "There's no stopping me!"

  8 Plot twists, e.g.

  9 Sorrowful

 10 Jack whose wife ate no lean

 11 One of many in a yearbook

 12 Theater lobby

 14 Danish shoe brand

 19 Spiny creature in a tide pool

 23 (Oh my!)

 24 Pines (for)

 25 "Yikes, that's bad!"

 26 Boy, in Barcelona

 28 Step before the majors

 31 Zoom alternative

 34 One concerned with oil prices?

 36 "That's incorrect!"

 37 Forbidden

 39 Itty-bitty mint

 41 Young male horse

 43 Leslie of "This Is 40"

 45 Mink's coat

 47 Indie film fan in vintage clothes, maybe

 50 Girls trip attendee

 52 Poseidon's domain

 53 "Nightmare" setting in horror films, briefly

 54 Actress Witherspoon

 55 Absurd

 57 "Eww!"

 60 Hawaiian root

 63 Spanish for "a"

 65 What an EMT may deliver

 66 Consumed

 67 Negative conjunction

solution