These were on my swap motor that came out of 2005 Tahoe 5.3 FF with 56K miles.

Ran them for about 1K miles. upgrading to 80# for boost.

PN - 12580426
EV6 plug

Approximate specs below
64mm total height
16mm body diameter
14mm oring diameter
48mm oring to oring


Looking for $75 shipped.