You are in a good place for fly fishing in St. Pete. I'd check out Sun Coast Fly Fisher's club. Many of the members there are with the FFF. Capt. Pete Greenan is a member, a Master Certified FFF Instructor and on the FFF Casting Board of Governors. He's also a good guy.
There is a lot of talent and experience in that club. I don't know if Dusty Sprague is there or at a club in Tampa , but he's also a great guy and Master Cast Inst. Many members are guides as well and spend a lot of time on the water.
Of the two 8 wt's, the BVK and the Lefty - which do you prefer with the WF8 line?
One thing I'd suggest is to work on the loop shape and loop diameter - on both back and forward casts, meaning you'll have to watch your back cast.
Change the loops from wide to narrow while false casting an easily controlable length of line. Try to cast with just enough energy to keep it aloft, yet straighten all the way out. Then add some more line.
A cheap click and pawl reel works well for this because it won't keep reeling in line with every forward stroke.
Get into the habit of shooting line through your line hand donut instead of letting go on the shoot. When sight fishing you will sometimes get tangles and can clamp off and shake them out with the line hand while making one additional casting cycle and not miss the shot at the fish.
Of course, before you get too tired, it's perfectably acceptable:no, it's absolutely impossible NOT TO just wind up and wing it as far as you possibly can, anyway you can, with every muscle you have in your body.
Just don't be surprised if it doesn't go very far.
Accuracy is important for sure, but he's in saltwater and wind, lots of wind. On the calm days, pressure waves caused by just rocking the boat will often prevent the bite, so the further from the boat the better in the calm. Also, some obnoxious fish will follow a fly literally tickling their nose for 40 feet while deciding if they want to eat it or not. If they get too close to the boat, "not" is their decision.
Windy days and cloudy water are different and they eat the fly better, but casting into a 20 mph wind 40' is like casting 90' on a calm day - assuming you can control the loop shape and even hit 40'. Distance takes on a whole new meaning in salt and wind. Like Lefty says, "There is no downside to being able to cast far".