Ok, took the spare, tools, and sub out of the back of the 370Z to weigh it last night. The pictures are terrible, sorry.
Bose Sub = 8 lbs.
Tools & Mats = 7 lbs.
Spare = 35 lbs.
Total = 50 lbs.
Also, side note. Probably one of the coolest looking spares I have seen, painted black and made by Enkei.