We just took our first camping trip with the new engine.

The only hiccup was that there were a few times when the coolant light
flashed, each time just for 2-3 seconds.  Maybe 3-4 flashes of the light
total each time, with a total of four occurrences out of 5-6 hours of
driving.

The first time it scared me silly and I immediately stopped and checked
everything.  Everything was normal.  Since we first bled the coolant system
after the engine swap our coolant level has been completely consistent,
with no loss or need to add any, including in the overfill container, which
has only fluctuated in level by at most 1cm between hot and cold.  All of
this was still the case so I decided some sort of electrical issues were
most likely.  (The pressure bottle has always been full to the brim.)

I regularly checked coolant levels in both bottles and everything remained
completely normal, with little-to-no fluctuation in levels.

Like I said when it did happen it was very brief---so brief that in spite
of having a 1.9l circuitry my needle never moved with the light.  There
also didn't much of a correlation with blinking and running temperature.
The engine was warmed up each time it happened but it didn't happen during
hill climbs, for example.  The needle was always in its normal location,
right on the LED.

My understanding is that although the 1.9 circuit is supposed to let the
flashing light go back off, that this is supposed to take 20 seconds or so,
is that right? In that case, since my light only blinked for a few seconds,
I figure I should suspect of circuitry or dash, and not the sender.

I should add that I have a recently acquired later style cluster with a
tach, although I don't think the cluster style matters from the standpoint
of how the light is supposed to behave.

Thanks for any advice!
Wes