Far too boring I'm afraid. It becomes really repetitive and merely a matter of jumping through hoops to get the required stuff. Finding all the secret levels is extra boring I'm afraid.
There we go. All survived with 2200 to spare. 5 anchor points used.
The trick is 1, to triangulate. 2 use bits of ground which don't have anchor points. 3. Build it kind of section by section using lot and lots of parts. When a section/the bridge is complete start testing which parts you can delete.
I did it to the point where I can't delete a single part of my design.