looks like you have a few more parts to gathering up..........
Almost 2.5” diameterI need a reference, how big are those pistons? 2"?
Looks like you and 230 Pilot found my problem. Thanks a million!!!So the plugs that cam out of mine are R for resistor the H which is 14mm thread, 7/16 reach into the combustion chamber with 13/16 hex socket. 10 is for small engine.
Your plug is non resistor L=1/2” or .472 reach, 87 for industrial or special application, Y=standard nose projection, Ccopper plus electrode.
That extra 1/16 projection prob enough with some float to hit.