Most people do split up the signal, but actually your not supposed to run more than one amp on your remote wire. Your actually supposed to run a relay from one after the first amp hook up. You can make a choice between 3 options.
1. You can just split up your power using a T-block (distribution block)
for 2 amps (one wire goes in and 2 go out)...then just connect one remote wire from one amp to the next using 14 gauge power wire. The only reason I wouldn't do this is b/c I have seen radios burn up the remote connection b/c of the load of 2 amps instead of one.
2. Connect your first amplifier the normal way and run a 14 guage power wire from the 12V+ on the first amp to the remote connection on the second amp. This will turn on the 2nd amp when the first amp gets activated by the radio's remote signal.
3. use a relay to turn ( a lot more work), but it's the professional way and if you have never connected a relay it can be confusing.
REMEMBER....DON'T BE GHETTO AND USE SPEAKER WIRE AS POWER WIRE. THEY HAVE DIFFERENT PROPERTIES. YOU WOULDN'T USE AN RCA CABLE TO PLUG YOUR TV INTO THE WALL WOULD YOU!