like do not drive in on a Friday evening with all the other weekenders...nor should you drive out on Sunday evening...
The OP hasn't checked in since yesterday, but this advice is spot on. Driving through the Keys is a terrific experience. Just don't be in a hurry to get down to Key West. There are a lot of things along the way that shouldn't be missed.
Feed the tarpon at Robbie's in Islamorada.
Stop at World Wide Sportsmen (Bass Pro), not just to go inside, but walk the docks. You will see all sorts of fish
around the pilings, parrotfish, ornamental tropical, and on every trip down I have seen nurse sharks laying in the shallows.
Also, walk out on the old bridge at Bahia Honda
State Park. Spectacular view.
Pull over in Marathon, Get a burger at Burdines, get a view of Boot Key Harbor, probably the most sailboat masts you will ever see......
Then when you get to Key Weird, get a cigar, sit out on the balcony at the Whistle Bar and watch the weirdos go by. That's why you made the trip. If you want normal, stay home.
Also some of the OFF Duval Street places that are worth the side trip, the Green Parrot is a dump that has some of the best bands in KW. Dante's has it's own pool and the "scenery" is spectacular. If you want a incredible dinner, although pricey, go to the A&B Lobster House.
I told my wife the last time we were there, that KW is the place people spend lots of money
to get to, to eat and drink in places that would be condemned in their home town.
Can't wait to go again........