hi i had the same problem with the tram mission but i have now cracked it right go down the ladder kill all the solders then go to the black gates kill the to solgers on the other side now if you look left you will see two boxes one small the other large move the large one as close as you can to the lampost
make sure it is all so pushed up against the wall then move the small one so you can jump onto the larger one run jump up onto the lampost ( you must be quick or you will fall off ) once on jump up again then jump again and turn to your left if you do it right you will end up on the balcony now just jump over and play on if you cannot do this email me and ill send you the save game so you can play on
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