Need some help

[haten'chevs]

I've got a 99' 150 4x4 with a 5.4/auto payload package (7700) off road package with 3:73 posi which now has 110,000 on it. I've put headers on it, high performance COPS,new plugs, K&N FIPK, edge maf (put the orginal back in now as I thought that was the problem) and I also have a Flow master 3" into dual 2.5" exhaust.
It now runs terrible- the bottom end is just gutless and then at about 2500 rpm it REALLY comes on but on the low end or if it gets a load (like going up a hill) it acts like it has a miss or bogs way down. I've had bad cops in the past (owned it since new) and I really dont think its that because it idles smooth ect. ect. unlike any symptoms it did when I had a cop go bad. It runs fine when your not on the throttle (like when my wife drives it- I have a little heavier foot then she does) But if you really get on it, it falls on its face. Now that its cold (MN) it runs pretty good all the time- colder denser air seems to help it anytime.

I ASSUME I need a tuner to program it for the mods I've made-BUT which one? Its mainly a daily driver- But I farm so it does see some fairly heavy loads from time to time- the biggest being my pulling tractor at about a 9000 lb load.
Any help in the right direction is greatly appreciated-I'd like to get something bought ASAP.
Thanks
Rob