Joe-----
The bolts you have sound like the correct ones, to me. The "official" GM spec for these bolts is 3/8-16 X 1" and of GM 280M (SAE grade 5) material. However, GM bolts often measure slightly different than their "official" length. If you have a 15/16" long bolt WITH a section of unthreaded shank under the head, you almost certainly have the right bolts. Standard bolts of this thread size and length do not have such an unthreaded shank; the special bolts for the pressure plate-to-flywheel do.
The bolts are GM #838653. If you decide you want to replace them, many GM dealers will have these in stock, so you won't have to purchase a whole package.
Better yet, I recommend going with ARP bolts for this application. Use their #130-2201 or 230-2202, with the latter being my preference. These are supplied in a kit of 6 and are really not all that expensive. These are about the best quality bolt that you're going to find for the application.
By the way, I also use ARP bolts for the flywheel-to-crank. These are #100-2801 or 200-2802, with the latter being my preference.
The bolts you have sound like the correct ones, to me. The "official" GM spec for these bolts is 3/8-16 X 1" and of GM 280M (SAE grade 5) material. However, GM bolts often measure slightly different than their "official" length. If you have a 15/16" long bolt WITH a section of unthreaded shank under the head, you almost certainly have the right bolts. Standard bolts of this thread size and length do not have such an unthreaded shank; the special bolts for the pressure plate-to-flywheel do.
The bolts are GM #838653. If you decide you want to replace them, many GM dealers will have these in stock, so you won't have to purchase a whole package.
Better yet, I recommend going with ARP bolts for this application. Use their #130-2201 or 230-2202, with the latter being my preference. These are supplied in a kit of 6 and are really not all that expensive. These are about the best quality bolt that you're going to find for the application.
By the way, I also use ARP bolts for the flywheel-to-crank. These are #100-2801 or 200-2802, with the latter being my preference.