All changes to tower
| Date | Change | Source |
|---|---|---|
| 9 Jun 2018 | 1,4: canon info amended | Tim Jackson via 00012910 |
| 2 Jun 2011 | 1-4: turning, frame id added; frame info added | Andrew Higson via 00009389 |
| 3 Dec 2006 | Tenor note & nominal (B-33c) added | Nick Bowden#68 (ex GAD NBR spreadsheets) via e-mail |