Hooking up a sub & amp to the stock Bose while I wait for my new gear

[TonkaH2]

I'm waiting for the bugs to be worked out of some new equipment -and waiting for crafty installers to figure out the ins and outs of tearing up an H2. But I don't want to be without my bass, so I went ahead and installed my sub box and amp. The only outputs I could find don't have variable volume... does anybody know which are the right line outputs?

-Jack
Yellow H2 adv. pkg.
Alaska to ??? June '03
www.sunspotnatural.com