as far as i know. HLS exist on all LEFT HAND drive Z in the US. RLS came only in 260z. the only way to tell if it's a california car is to find the stick on the hood (if it is original hood and sticker still exist)
that shop is super busy. leaving a message wont get you anywhere. you will have to try to get a hold of kevin. a very nice gentleman. took me 2 weeks and 5 phone calls to get a hold of kevin and the check