SkyVector question

Student pilot here with no experience, but a lot of book-learning. I have a question about using SkyVector to do a simple flight plan.
So, I was goofing around with making a flight plan to fly from my home airport in TN to visit a friend of mine who lives in Sarasota FL. I chose as waypoints, first, the Ocala VORTAC, then down V157 to the Lakeland VORTAC, then turning to a vector of 218 which takes me to SRQ. All fine and good... until I'm looking at the VFR map and noticed that that last leg takes me under the 6000ft outer shelf of TPA. I had set my cruising alt to 8500. SkyVector's NavLog has my TOD set at 14 miles out, which is has me busting Tampa's Class B for quite the distance. Like, 30 miles of it. So I went to adjust my descent point.... IS there a way to do that? Because if so, I can't figure it out. I'm sure in the real world, you just contact Tampa Control and ask for flight following by the time you hit the Lakeland VOR, and unless there was a problem, they would grant permission to enter the space, but this is more a question about the capabilities of SkyVector. Any help would be appreciated!

I don't think Skyvector has the capability to do so. Generally, the flight plan doesn't need to be that precise for a VFR flight especially. You are going to fly different altitudes based on where the clouds are at as well.