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I wouldn't mind seeing some photos of your engine bay extra wiring if that's cool. If possible can you include some photos about how to upgrade the alternator to battery? I am not really sure where on the alternator I'm supposed to connect the wire.
And excuse me if this is a stupid question, but strut tower? What is it?
I wouldn't say the name brands are "worth" the extra money, but they are slightly better. The name brands are usually more flexible, have better quality jacket/cover.
I compared Stinger vs some eBay 0ga... The eBay wire had a little less copper and a thicker jacket/cover but wasn't quite centered in the jacket properly.