I just cut 2x4 to 16" length, then cut corner to corner(45*). I used 2 pieces of 1/2" of plywood straps. Bottom one was used as a "stop to keep head from sliding down". The other one was used as a "wedge" until valve/guide was perpendicular (or close).
Hope that makes sense.
Got one head on and was going to assemble with new ARP head bolts #1443602, but I read in their instructions about using thread sealant if going into water. Do I need to worry about sealant/water? $30 for a tiny damned tube.... :BangHead: