Slant six spark plugs and numbers

Take a few pics, try to slide the phone down to show the spark plug areas if you can.
Not really sure what you have there.
Aren't the plugs recessed the aluminum sleeves?
Either one of the 2 spark plug sockets (5/8 or 13/16ths) with a short extension should work.
A swivel 3/8ths drive ratchet may make getting to those plugs a bit easier.
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