Stereo & Electronics - firebird electrical / stereo issues

i am in the process of installing a battery isolator in my bird and i just finished wiring it up here are the install directions.

http://www.surepower.com/pdf/180012n.pdf
need adobe acrobat to view

page 2 right below #9 is the wiring diagrahm

now my issue

i just finished wiring up the isolator.

i cut the wire from the alternator to the battery and ran it to the isolator at the correct terminal (A).

i then ran the wire (all 4 gauge) from the correct terminal to the main starting battery (1).
wire was also run to the second (stereo) battery (2).

i then hooked the "e" terminal up to the ACC fuse slot inside the drivers side door for switched power. the battery was disconnected while wiring was done.

now when i go to start the car it will crank and crank and crank. it started the first time but even mapulating the gas pedal i couldnt keep the car running.

also while the car was momentarily running the volt meter in the dash was only showing 11-12 volts.
i am recharging the battery now.

please give me ideas on what to check

thanks