Hi Grilled,
I had exactly the same problem, I played this for ages over and over and always too many resistance fighters were killed. I finally managed to get through this just now, I will try and describe what I did, which may help you. I did it on "marksman" setting.
OK! after climbing the stairs, kill the three soldiers, I use a couple of grenades. After the cut-scene, move just inside the archway at top the stairs, and take up position to the right where there are 2 medipacks, DONT go to the far end of the building yet, remember, just inside the archway at top of stairs on the right.
Using binoculars look to the far distance and to the left by some rubble, four soldiers appear, two turn right and continue parallel with you, and two come straight down and to your left. Kill the two running parallel first, and then the two down to your left. Then a lorry appears in distance (near where the soldiers came from) with four more soldiers in it, I managed to kill the driver while moving, or you could set a tripwire if you can see the route the truck takes. In my mission, again two went right, (kill these first) and two doubled back left again, if you kill these you should get objective complete mission. I quickly saved here!. You then have to go to the far end of the building and take out a few more troops in the courtyard. Hope this helps in some way. Its a matter really of trial end error, the best tips I can give, is get to know where the soldiers appear, and which way they go, its a matter of killing them before they get near the resistance fighters and use binoculars to pick them out. I think the main problem is it is very difficult to spot where they are, and having enough time to change between binoculars, sniper rifle, and getting off a few shots. Best of luck, great game isnt it!! Let me know how you get on.
This message was edited by snipey99 on Jan 23 2008.
This message was edited by snipey99 on Jan 23 2008.