Info provided by Calvin of Nivlac57 Youtube Channel

Head Studs

We have been using Head Studs that are spec'd for a Gen 3 (97-03) LS on these engines. Make sure you are getting the studs that have the long and short studs.  In most cases you will need a spacer to make them work. See below. I recommend the ARP ones. The Speedmaster (Chinese) studs like to stretch.

Here is how the compare to the Speedmaster Head Studs (ARP top, Speedmaster bottom). You can almost get away without a spacer on the Speedmaster stud, but your mileage may vary. You will need a 3/4 inch spacer to make the ARP work.

Below: ARP studs with 3/4 inch spacers.

These are the spacers I use. Note, they come in pairs.

Main Studs

Once again, we are using studs that are intended for another application, but it works, so who cares. In this case we are using ARP studs meant to be a head stud for a BMW/Mini Cooper 1.6L. They are just barely too short (like 1 thread) with the supplied washers, so we harvest the washers off the factory bolts (since they are thinner) and drill them out to 10mm.