Probably the easiest way to do it would be get a set of rca splitters so you can run to both amps, get a fuse block so you can split your power wire, and find two ground points and simply run the remote wire to the other amp. I'd recommend using two separate ground points to ensure the amps are properly grounded.
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"I'm not driving too fast...just flying too low"
Mine:
-87 ranger- broke
-03 SB Cobra vert- 2552 of 5082 Born 02/25/03
Our's:
90 7up vert - new project