I see they also make a 2065180.
If I had iron heads, I definitely would have used it. The 195F stat, 11:1 static, 9:1 dynamic, 13:1 afr, 32° timing and 91 octane did show a brief 3-4° of knock retard on a WOT uphill pass and a couple other brief knock retard events lugged down uphill. The timing retard was showing up with the engine around 205-207F when it was working pretty hard uphill. Other than that it cruises along nearly effortlessly. I will pull 1 degree of timing out of the coolant table at 194F and 2 degrees out at 203F and above over what it pulls stock, then retest. I am pulling it out of the coolant spark compensation table because it runs 32 degrees just fine at 176-180F. No reason to neuter the engine all the time for something that only shows up when it is hot. Also if you do not see a little detonation while dialing in the engine you either have the tune super conservative giving up power and efficiency or a dead knock sensor. I did not check the mileage other than what the mathematical equation I wrote in the HP Tuners scanner showed which is fairly accurate. After 30 miles it was showing 18.96 average. I was driving the back roads out by my mom's house in the Possum Kingdom/Graham, TX area. The roads are windy, hilly, wash boarded, and just poorly maintained. I also had a pretty strong 10-15 mph frontal crosswind for half the trip that was noticeable in the steering. Its hard to judge the mileage on them compared to nice flatter interstate.