I have some info That may help.
1)Part # 2514701 (They are Ford Cosworth studs, but are the same spec for the TDI)
2)I don't know if its the same for an IDI, but if you google ARP and call they may be able to tell you.
3)I used the VW torque sequence ( I don't know if its the same as the ARP sequence )
4)You can order them through most parts stores.( I bought mine through Lordco parts)
5)I paid around $300.00
6)Final torque depends on the lubricant you are using.If you use ARP molly lube final torque is 80 ft/lbs.
If you use 30w engine oil final torque is 120 ft/lbs.
Clean the threads in your block realy well, then put a light film of lube on the studs. Thread the studs into the block hand tight. Slide new head gasket and head on to block. Lube the studs, washers and nuts and torque to 30 lbs in sequence, then 60 lbs, 90 lbs, final torque 120ft/lbs(with 30w oil).30,50 final 80ft/lbs(with molly lube).
Even with ARP studs I wouldn't run the boost past 35 psi. I blew my head gasket at 40 psi.
I am using a twin turbo set up, so at 40 psi there quite a bit more air being pushed through than a sing turbo set up, so you may be able to get away with 40 psi