Align Bridge Post with base plates

Hi Experts

I would like to get your help for the Bridge posts on given surfaces.
attach is files. in rhino file there are top surfaces and a post that could be placed on top of each surface match bottom of post plates and i have marked a point on insertion point on post.

kindly share your experience.

Best regards
Muhammad IsmailBase Plates.3dm (897.6 KB) Post (10.1 KB)

Something like this? Post (13.0 KB)

Hi Mark.

A very Big Thank you for your time and help.
i have checked but the post plates are not matching with rectangles as bottoms so orientation not right.
but again thanks very much and have a great day.

Best Regards
Muhammad Ismail

Here is a different approach, in this definition a plane is constructed from the vertices from the base plates: Post (10.6 KB)
In every row I have rotated one base plate because the orientation differed from the rest: Base Plates_ME.3dm (904.5 KB)

It’s just an approach, so I hope it’s helpful.

Yes Mark. indeed it makes sense. look exactly what i was looking for. bec as Bridge profile vertically changes then the posts will orient similarly.
So again thanks very much and hope will place another question later.

Best Regards
Muhammad Ismail