We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember PeterC
saying something like:

A cheapo Black and Decker jigsaw and a packet of blades reduced mine
to manageable segments; cut into 4 parts I seem to recall.
The rivetted construction looks like armour plate but they are less
formidable than they look.

Exactly. It's not a Herculean effort to cut mild steel water tanks,
especially if attention is paid to putting a line of oil along the cut.

Might well get away with 1 cut along the centreline.

Quite likely.