Get to I-4 East (which can be a major ordeal from Clearwater as you are well aware.) Stay on I-4 to near the WDW area and merge right to the Greeneway SR 417 (follow the Airplane signs like your going to OIA). You will pass the south side of OIA. After the Narcoossee exit, you will merge onto the Beeline East (SR528). It goes to the port. The only thing to watch for on 528 is the split right after you cross the St Johns River. Make sure you veer right. It is well marked, including a graphic of a ship for the right and a space shuttle for the left. Follow the ship! It should be about 1 hour from the time you get on the Greenway to the time you get to the port. You will see the ship before you get to the exit off of 528. Really a simple drive, except for possible I4 traffic. Greeneway and Beeline do have tolls. It will cost about $4 one way all together. Hope this helps.