power and economy are at opposite ends. So, which do you want?
More power usually means more heat. Are you on the verge already of overheating on big climbs?
What climbs, just hills, or serious mountains?
Chips are different than tuners, which just dump in more fuel.
The cheapo chips u see on amazon are just little things that cut the voltage lower, spoofing the ECU. I spoofed my foreign truck by cutting voltage from the MAF. This had the effect to lean out the fuel mixture. Both power and economy increased. Exhaust temps increased but did not matter on a small truck.
If you lean out your fuel mixture your engine temps will increase. I dont think you have enough margin to handle more temps.
My method was to use a pot and manually cut back the signal which made the CPU think there was less air flowing through the intake, so it put in less gasoline (leaned it out).
I could feel the power boost as I slightly leaned out the mix. mpg went up 2-3 mpg in my particular instance, You will not see 2-3 mpg increase on a V-10.
Tuners could range in the $700 range. not worth the cost, and that is if you can do the install yourself. It is quite involved, not for the novice. I put a tuner on a turbo diesel, but a diesel has a lot, a lot more potential than an old ford gasser.