Shine a light through the Apple logo do you even get image? Does the board even chime?
so you get backlight but no image since you state the apple logo lights up. try a known good screen check lvds cable for damage. any damage on lvds connector itself?
measure those resistors first if they are good then check u7701 on pin 5 sometimes feedback ball will be missing then you'll know you must replace the led driver and run wires. Either way if i were you id inspect the board and replace or reflow and clean anything that looks badly corroded and damaged before you go measuring. try reflowing led driver as well.
disconnect power from the board and measure them on the board. no need to remove them.
no r7731 is ok if it was higher than the rated resistance then yes it would be bad. make sure you reflow the led driver until you see it move (dance around) add a good amount of flux. i always have my hot air station at 400 degrees and 80 for air. whatever works for you though.
make sure you check if ball on pin 5 is even there.
make sure r7704 is measuring good too and check voltage on both pins of d7701
make sure r7704 is measuring good too and check voltage on both pins of d7701
check if you get an image or backlight.
check if you get an image or backlight. if you still dont get an image either an apple logo or flashing folder by flashing light onto the apple logo on the back of the screen then check continuity on pin 18/19 of lvds connector and pin 2 of L8304 and check voltages on pin 18/19 of lvds as well.