I was desiging my hexapod and plan to use SSC-32 & BB II + BAP. so I want to know it dimension. most important is dimension of those 4 hole for 3m screw.
The boards are 3" by 2.3", and the holes are 2.7" by 2".
Alan KM6VV
Thank for your reply. I want to confirm my understand for the hole. You said the hole are 2.7" x 2" this mean each hole will have distance from edge to center of hole = 0.3" and hole dimeter = 3 mm. (as show in picture below)
Not exactly…
The boards are 3" by 2.3", and the holes are 2.7" by 2".
3" - 2.7" = .3" which needs to be halved, so the holes are actually spaced 0.15" in from each edge. 
Here’s the drawing I use.
Board outline in dashes. Offsets to edges typical.
Dark “curvy” contour is a cutout, if desired.
You might want to very the hole size to fit your mounting hardware.
http://www.MarconettEngineering.com/BB2_Dim.jpg
Alan KM6VV
Thank you. Now I’m clear.