How to fix this UV black magic fuckery?

[funky fred]

The UV mapping is different for every one of these things i placed on the top of the wall and on every single surface, so it's completely impossible to have them all lined up nicely. Some even at different rotations. Is there any way to fix this easily or do i have to manually edit every single surface at every angle for this to work?
There was a solution I tried which worked at first and it looked normal, but then when i used it shadows didn't draw on it so it was broken anyway