Thanks again joe for another tip "shortcuts"
If any one is interested i found some good videos for sketchup at Home - Harwood Podcast Network. I do find it a fantastic program and it's free. I've found the easiest way of transferring holes from one component to another is to draw a line at 90 degs from the centre of the first hole through the other component and then draw a circle on that components face. I tend to leave things at that because i find it difficult repairing "punched through holes" if it needs to be moved.