Not enough information to advise you correctly, but here we go
If you rented a fairly large backhoe, those 6-10" stumps will pop out of soft ground like carrots. /forums/images/graemlins/wink.gif If you didn't, well then it's gonna be like 4-5 per hour.
You don't mention whether you will be burying the stumps, hauling them out later, grading at the same time etc. If you are burying & grading at the same time, you will be lucky to get an acre done in a week.
I haul the stumps to my stump dump (on my property) every other day of digging. (dig 2 days, haul 1 day)
Try to work from a main road that you envision will be firm enough to stand the repeated traffic. Layout the road (note you aren't making anything here, just picking the path) so you will not be digging any stumps in the middle. If there are stumps in "your road", leave them for last.
Back as far off the road as you can (within reason, plan more roads as necessary) & start digging there. I pile up 4 or 5 stumps depending on their size, then bring them the 200 ft to the side of the road.
If I only had one week to dig 5 acres worth of stumps, I would pray for sun, strap a coffee maker to the side of the truck, plan on working that tractor 18 hrs a day, & hope the neighbors are really far away.