You have to get the following head studs: AP2.725-1B

These are 2.725" long but also have a longer coarse threaded portion: 1.150" vs. 1" (screw in deeper into the block).

Summit can order them for you.

The studs come in an ARP kit as well - part number for the kit is 134-4201 (small block Chevy). The kit comes with 16 of the shorter studs and 4 studs in 4.150" and 14 studs in 4.750"