#1
I want to get two new texas heat speakers and i dont know what ohm rating would be correct. Since the cab is 16 ohm's im assuming the sheffields in it would be 16 ohms too right?
Current Setup

Schecter Blackjack C7
Epiphone Les Paul Custom w/ EMG 81/85
Peavey 5150II Head
Peavey 6505 Cab w/ two Eminence Texas Heat
Epi PR5-e
Hot Rod Deluxe
#2
Could be all 4 ohms in series, or 16 ohms in in parallel/series configuration.
#3
I'd put my money on all of the speakers being 16 ohm, to be quite honest. You can always disconnect one and test it with a multimeter to get an approximation - you will only get resistance rather than impedance, but the difference should be big enough that you can assume what impedance the speaker is.
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