Wiper Problem

[Dempseyyaris]

Hi.

I have just replaced the front wiper linkage on my girlfriends 2004 Yaris and the motor is running fine. However I am having difficulty in aligning the wiper arms so that they sit almost parallel to the bonnet when in the off position and out of the drivers way. It seems to be that if I put them almost horizontal when off then they try to slide down the bonnet before clearing the window of any rain, when turned on. Is there any tips or a specific way of doing this? Also does the motor return the linkage to the same stationary point when switched off despite changing the position at which they started from before turning the wipers on?

Thanks