A solid hard-Friday/Saturday time for me, and that's with using the check function a couple of times.
I'd like to echo a lot of what Joon wrote, with a few exceptions.
Joon is right about 40-Across. "Due for" matches with "in for", so the clue for DUE should read [In (for)]
11-Down was one of the first answers I filled in. Since neither BOOM BOOM WASHINGTON nor FREDDIE WASHINGTON fit, it had to be VINNIE BARBARINO. (Joon, that's from "Welcome Back Kotter". Required viewing for all school kids in the '75-'76 and '76-'77 seasons.) I, conversely, had no clue about 3-Down. (I know "Basket Case" and not much more.)
I got 24-A right away and it looks fine to me.
Most of it was fun-tough, except for a few spots. I don't understand the clues [Use a diaphragm] for INSPIRE or [Pet] for SNIT. Also, the clue at 7-D ["Nothin' doin'!"] seems to clue NO WAY or NO HOW or GET BENT. A SNAP needs something more like ["No prob!"], but maybe that's a case of the ol' seperated-by-a-common-language syndrome(?).
The [His ___] NIPS / DANI [___ California] crossing also required letter-roulette/check. Not familiar with either one of those phrases. (The only DANI I know of is Dani Harrison, guitar-playing son of George.)
Didn't know of that particular ELSA, and still don't know who ANGE and ENNIO were. Don't know what comic Fred the BASSET is in. Never heard of ILLYRIA and needed every crossing, playing letter-roulette at the STOAT crossing to finally finish the puzzle.
Loved a lot of the clues/entries that Joon pointed out and I'll specifically mention 37-D, 39-D, 35-A, 21-D, 6-D.
All cluing aside, the only fill-centric problem area (publication-wise) that I see is the ENNIO-STOAT-ILLYRIA area. It'd be hard to make a foothold entry out of any of them without changing the corner to STOAS / DOS.
EDIT TO ADD:
P.S. What the @#$% is "His nips"? Oh, sure. I could google it. But, as a child of the '70s, I still prefer the good ol', pre-internet "explain yerself" approach.