Thanks for the responses everyone. I figured, since most of the semis were going faster then I was, that the FE gains would be either negated or worse from the increase in speed even though I don't have as much wind resistance.
So, I got here and it took me just under 5 hours to do a normally 2 1/2 hour trip
. The posted limit was 70mph (ouch) but traffic was light so I set the cruise control to hold me at the speed that got my RPMs to 2000RPMs and just left it there for the most part. I tried a little DWL but the route I took had VERY few hills so it didn't make a difference really then having cruise control on. I also found a semi doing just 60mph (i was doing around 57ish) and I noticed that on uphills he slowed down a bunch and on downhills he sped up a bunch...aka he was doing DWL stuff for his semi. So I hopped on in behind him so that I was more visible to cars coming up behind (at 80!) and I could keep the gas pedal steady with him and not cause any problems behind me.
I ended up getting about 34mpg on this tank which was mostly city driving, only the last half-ish was on the highway. The return tank will be the one to know how I'm doing on the highway.
Aeromods are coming, yes, I promise. However, I'm hesitant to do any until I get my scangauge because I don't want to just be doing aimless aeromods and not have any way to back-up my claims that they improve FE to people who ask.