This was one tough puzzle. Stacks upon stacks, as well as some very fresh fill. There wasn't much that could be Googled, but those were spread out enough that it was possible to get a toe-hold in every area.
There were a handful of gimmes, so at least I was off to a good start.
15A: "__ as directed" (use as).
30A: Bills are in it: Abbr. (AFC). Big pat on the back, please. Not just a sports clue, but one with an odd clue.
33A: Bibliographical abbr. (et al).
34A: Venue of many Richard Petty wins (Daytona). In my former life (that is, not with Don) I lived in Daytona Beach for a short time. We didn't go to the races, but we did get to drive on the beach...a very cool experience.
65A: Rich spreads (pates).
3D: Relating to babes (neonatal). I was sure I was wrong with that one, but I wasn't.
4D: __ City, seat of Pasco County, Fla. (Dade).
5D: Right hands: Abbr. (assts).
6D: 1945 film musical with the song "It Might As Well Be Spring" (State Fair). For many years, our local amusement park had the Tilt-A-Whirl from State Fair, so I felt compelled to ride it...not a good idea. The park is no longer in business, and the ride has moved to another amusement park.
24D: Creme Egg maker (Cadbury). Despite the fact that they contain chocolate, I have always found them personally disgusting.
53D: Diamond protectors (tarps). Sports-ish clue, got it...hooray!
Not much, but things progressed from there.
I also had a couple of wrong answers in place that definitely sent me in the wrong direction.
45A: One working on a board (ironer). That makes sense, but I had planer...which also makes sense and fit with a couple of downs.
58A: "I'll give you __" (a hint). I'll give you one...you could also have a call or a ring. I had both.
14D: Green stinger (nettle)...oops, not Hornet.
43D: On the sundeck (basking)...I had tanning.
I liked the clever cluing in 1A: Back-and-forth (Q and A)...couldn't figure out what word would end in A, though. Also 17A: Apple storage devices (iPods), 36A: First-class handouts? (syllabi), 49A: Poses in a studio? (yoga), and 57A: Letters before a street name (aka)...better known as a/k/a.
Some of my favorite across answers: 16A: Product identifier (trade name), 18A: It maintains a proper attitude (autopilot), 38A: Herd-thinning menace (rustler), 42A: Semirural, say (exurban)...had this fairly recently and was pleased to find the mental note I had made, 60A: Colloquial (idiomatic)...that word always makes me think of someone who acts like an idiot...automatically, and 64A: Logic's counterpart (sentiment)...I could write a book on that based on thirty years with my logical husband.
And the best of the downs: 1D: Nitpicking (quibbles), 2D: Harshness (asperity), 7D: Cutting out? (truancy), 12D: Costa del Sol port (Malaga), 35D: Does, as business (transacts), 39D: Probe (look into), 40D: Bring about with some effort (engineer), and 41D: Cavalier evaluation? (road test)...just now saw the cleverness of that one.
Time to call it a night. Here's the grid...
...and I'll see you tomorrow.