Getting the measurements right is important, but more important is getting the second half to exactly match the first half. We tried measuring out the second half but gave up and invested 4 days to shuffle the steel so we could get an exact copy. And we are glad we did.
1. Lift B off of A
2. Drag A into city park.
3. Flip B over and lay it down.
4. Drag A back in on top of B
5. Use A to cut outside of B and mark the darts.
6. Drag A into city park again.
7. Lift B, flip it back over, cut the darts.
8. Drag A back in from city park.