I was given an interview date the last time they advertised ( although family made me decline due to sudden onset of earthquake phobia). Interviews were to be held in manchester. The guy i spoke to at Sierra seemed ok (Camillus Byrne an Irish lad).
Sierra were acting as recruitng agent for
R.Royce who had taken over a plant in Oakland which maintained Alison 501's & T 56's - not sure if there may have been an on wing support element as well.
I did'nt get into money as i did'nt take it any further but you need to be looking at a wage of around $20 an hr ( not much by UK standards). N.California is pricey & state Tax is about the highest in the US.
Hope this helps, Cheers
Ragspanner.