Hi there, so I have a 1960 with the stock t75s. I found online two used v30s for 150 and was thinking about doing an x pattern, but the v30 are 8ohm and I believe the 75s in there are 16. I also don't know that much about wiring so I was planning on just copying the other speakers. If this is possible, how will it affect the total impedance? How about the wattage? Thanks!
probably safer if you use the same impedance

different wattage/power will go to different speakers. IIRC double will go the lower impedance speaker (series-parallel wiring, like your cab likely has, might well affect how this works, too, and if so this is getting above my pay grade). so assuming you have a 100 watt head, ~67 watts will go to the 8 ohm speakers and ~33 watts will go to the 16 ohm.so that'll be 33 watts per v30 (fine) and ~17 watts per g12t75 (also fine). in terms of not blowing speakers you'll be fine, but the problem is double the wattage will be going to the v30s so they'll likely overpower the g12t75s in terms of volume.

wait for the correct impedance v30s to come up, basically.
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