Here are 19 used GM factory original Pontiac D port head bolts. They are original for the 389-455 cu." engines. They measure 1/2" x 13 thread size, 3 5/8" long, and 11/16 head size with the letter C cast on every one, see photos. They are grade 8 bolts in excellent condition. They are $2.50 each or $25.00 for 12 or $35.00 for all 19 bolts.
-----They can be picked up at
428 Grasslands Rd.
Valhalla N.Y. 10595
Or I can ship them if you like. Please message me your Zip code so I can calculate the shipping charge.