The better seats are higher up... The higher, the better (& more expensive)! Draw a straight line down pit road, & extend it both ways through the stands. The seats on the starting-line side of your line are more desirable, & the higher up you are, the more track you can see (& the more $$$$$$ you spend).
I went to Daytona in Feb back in '88 & '89 (camped for free at the airport in Deland where I was skydiving for a 10 days surrounding the race) & the seats were in turn 3, looking down pit road in the top row of the mid-price seats($50/each back then) section & you could see everything except the low groove in turn 2. Don't expect to get seats like this. The guy that supplied my seats had been getting the same seats (10 in all) since the 60's. Usually, you'll end up right down on the track, & all you can see is what happens right in front of you (IMHO, not worth the $$ & crowds & traffic jam leaving). If you do go, don't run for the parking lot when the checkered flag falls! Hang around for at least 1 hour & let the mass exodus abate some.