I've acquired one of Rob Guyatt's "flash" units (an RMG Digital Voltage Display)
and installed it in the lid of my pot. It works perfectly, and makes for
an altogether more relaxed day of sailing.
It is quite simple to cut a rectangle into the lining of the
SAILSetc pot lid, and then to fasten the flash unit to the inside of the lid
with a strip of double-sided sticky-backed tape.