DONT DO IT MATE 

Even if it is in the manual does not mean that the production games were produced with it therefore NOT original.
Maybe the games you have seen them on were very early release games, I'd seriously think twice about it.

You have a lot more pinball expertise than me so I'll take that advice onboard thanks for the tip.
Out of curiousity why don't you like the post's and wouldn't it help with ball drain? I can understand if there not factory but if they are and someone has just removed this one when doing the restore (which is my guess on what happeneed) I can't see the problem. I must be missing something?
Thanks..Tim