q1: Doesnt look like you need a high output alternator. If your battery and alternator is in good shape now, you are cool.
q2: I am not familiar with the Accords, but they should have a rubber grommet(sp) where wires are already running through the firewall. People usually just use that hole.
q3: You can spilt the remote turn on when it gets into the trunk into two. It should turn on 2 amps just fine. If you are using it to turn on more than two things, you should probably look into using a relay.
__________________
.