I believe it's the December 1968 issue of Road and Track that tested four full-size cars in one article. The 69 Wildcat was one of them and I remember the 0-60 time was just over 9 seconds.
.060
.060" (1.52mm)
.060
The gap is .060
.060 inch. or 60 thousandth
plug gap is .060
.060"
.060 thousands
.060" is what the parts stores say.
.060 (Double-check with a Buick dealer's service center. They'll know for sure).
2000 Buick century gap for spark plug 3.1l
.065