if used without washers the 4 special main cap bolts will not brinnell the tray because the tray sits on top of them. and when I use studs I do not increase the stress by 50-70%
My statement on the stress relates to using ARP studs (and bolts) with their lube vs dry torqued regular bolts. You don't TORQUE them that much higher, but just using the ARP lube on threads and under the nuts increases the clamping force (and thus thread stress) by about 40-50% even if you used the FSM torque level, and using more torque as per ARP's instructions adds more on top of that.