The entire discography of Elvis Costello.
(and here I thought this thread was going to be about double entendres in the music itself, which unfortunately I can’t think of any examples.)
Okay, I just thought of one that’s sort of appropriate. In A Praise Chorus by Jimmy Eat World, one of the lines is “Why Did We Ever Meet?”, and the line is sung by Davey van Bohlen of the Promise Ring. And the bassline to the song itself is similar to the bassline of the song Why Did We Ever Meet? by the Promise Ring, and the song itself is about musical nostalgia, so it’s possible that Jimmy Eat World was using the music to refer to the theme of the song and the lyrics.
That was gonna be my answer too.
And how about these lyrics from Alabama (Feels So Right):
“Your body feels so gentle
And my passion rises high.”
And these from Ricky Lynn Gregg (If I Had A Cheatin’ Heart):
“Your eyes tell me you don’t mean maybe
Oh, baby, you’re makin’ it hard.”
I’m surprised that no one’s yet mentioned Sugar Walls by Sheena Easton.
Jackson Browne’s Red Neck Friend
Here’s a snippet:
Honey you shake and I’ll rattle and we’ll roll on down the line
We’re going to forget all about the battle
It’s gonna feel so fine
’cause he’s the missing link, the kitchen sink–
Eleven on a scale of ten
Honey let me introduce you to my redneck friend
Ruth Brown - I’ll Keep Sittin’ On It
“So if I can’t sell it,
I’m gonna keep sittin on it.
I ain’t gonna give it away.”
Did Ruth have an antecedent for her “it”? A couch, a chair, or like that?
'Cause if it’s just an “it,” that ain’t innuendo, that’s just it.
She actually did another similar one, “Peter the Meter Reader”:
Then at the end:
I forgot about Heart’s “Sylvan Song/Dream of the Archer”. On one level it’s about a fantasy-themed dream about chasing a pot of gold through the forest, and on another level it’s about…“singing strings”, “woods”, “releasing the arrow”, and, well, chasing a pot of gold through the forest.
“If I said you had a beautiful body would you hold it against me?”
This is a good place to nominate my favourite ever song title, by New Bomb Turks, but alas it’s nowhere near innuendo:
Drunk on cock
Yes, she did. There was a backstory about secondhand furniture and a fella interested in a particular chair. She was angling for a better price. 
The Who’s Pete Townshend wrote Squeeze Box to celebrate learning to play the accordian without falling down. Like Magic Bus, it was based on a simple sexual joke, and it took about 15 minutes to write.
Mama’s got a squeeze box,
Daddy never sleeps at night.
Kate Bush,
In the Warm Room"
In the warm room
Her perfume reaches you.
Eventually you’ll fall for her.
Down you’ll go
To where the mellow wallows.
In the warm room
She’ll touch you with your Mamma’s hand.
You’ll long to kiss those red lips,
But when you do
It’ll feel like kicking a habit.
. . . . .
In the warm room
You’ll fall into her like a pillow.
Her thighs are soft as marshmallows.
Say hello
To the soft musk of her hollows.
. . . . .
The disco group Musique had a song called “Push Push in the Bush.”
No, that’s not really innuendo, is it?
Many of AC/DCs song can’t really be made any dirtier. Just more plain.
Givin’ The Dog A Bone
Let Me Put My Love Into You
And of course, almost every single lyric from Spinal Tap sounds like it was written by a 13 year old boy.
Then there’s “He’s Got the Cutest Little Dinghy in the Navy” Sung in the late 40’s or early 50’s, by a Ruth Wallis, it’s the epitome of double entendre.
Ah, yes. She was talking about a sofa. What else?
Ignore that post. It’s what Asknott said.
All of the Bloodhound Gang’s songs.
I tried to pull out before I posted, but I got too excited.
If I get you in the loop when I make a point to be straight with you then in lieu of the innuendo in the end know my intent though; I brazilian wax poetic, so hypothetically, I don’t wanna beat around the bush…