Just a quick note:
A fair few vessels were designed before everything got set in stone--specifically, I had given different names for the weapon systems known as the Light and Heavy Self-Destruct Charges (because I initially thought of them only for a specific role--the Heavy SDC was initially named the CABINET Mount Self-Destruct Charge as they were intended to self-destruct the platform after their CABINET Mount had been discharged to prevent any knowledge of who'd employed such a device).
Instead of changing the weapon names in the spreadsheets I simply replaced the mentions of the previous weapons with either Light or Heavy Self-Destruct Charges in the Drake Notation files I'd kept for document assembly, but forgot that I'd called them Self-Destruct Charges and instead called them Self-Destruct Mechanisms. Rest assured, both are correct, just a slight naming difference.
Also, such Self-Destruct Charges/Mechanisms do not count as weapons per se when designing Archaic vessels--they're simply a catastrophic-fail device installed on the primary powerplant of the vessel. The ASBC capital ships actually have their oversized powerplant exposed to vacuum to enable a far more effective self-destruct (to prevent Berserkers gaining access to their computer cores and crew). Thus those Archaic vessels with SDCs in the Aft or L arcs are correct, it's just the powerplant having a catastrophic-fail device installed.