Thanks, Jason. To counter, I never count my time, unless it interferes with work, i am either making money or wasting time kinda thing. my time is how much i save, make sense? However, not really my point, just kinda a number tweaker. Add to that, as a daily driver, I drive appx 15k a year, maybe more. Recovery mileage is not a real issue. Part of the question stems from my 87 cc dually, (2wd changes things, i know) I get 11-12 mpg with the stock 454 (plus 40 series flowmasters and a flipped air cleaner) and sm465 and 3.73 rears. I am not sure yet the milage of the 89, as the engine is out, but will be temporarily using the 454 from the 87 (the 87's frame and body are wore slap out from being a rodeo stock truck-will be parting it out soon, with most of it going to scrap). The 11-12 seems high (but has been repeatedly verified), but is 15-16 that unreasonable? I am also considering a vortec 8100 swap with a tune, the idea being it wont work as hard as a worn out 454, or stroke the 454 it has in a rebuild, and upgrade the injection/induction system, with a turbo system possible. More power when I do pull, and should be more efficient when I am nice to it. In addition, any thoughts on the 4l80e-six speed planetary set swap? basically the tci 6x transmission you make with your own case....i will find the manufacturer for that for those who are interested. I have too many ideas for this truck, trying to make sense of how to go about it. Thanks, guys.