Attached are the Static Port pages from the 320 build manual  I believe the same locations would be used on a 235..  I suggest that you place ports on both sides of the plane and Tee them together to eliminate any bias.  Is is also wise to add a Tee at the lowest point with maybe 6-8 inches of a tubing tail, sealed at the end, to collect any water that may possibly enter the system when parked outside in a heavy wind-blown rainstorm.

 

Scott Krueger