02 Tahoe amp upgrade

Hello, I have an 02 Tahoe Z71 with Onstar and a factory sub. I am wanting to upgrade the factory amp behind the glove box. I have heard there is an adapter harness to plug into the factory wiring at the amp. I am triing to cut as few wires as possible. Also I noticed Soundgate has a Type 2 Line Output Converters, do I need these?

Does anybody know how to upgrade the bass on this vehicle?

the easiest way to upgrade the bass is just put in a sub and run it off a line out converter off your rear speakers.

I have a 2002 Yukon and what I did at first was to have a custom box built almost the same size as the sub box in the left rear quarter panel and upgraded the 8" sub. Then I took the wire from the sub and ran it to a 360 watt amp (mounted under the rear seat)using an AudioPipe NR-100 High/Low Impedance Adapter, I ran it to the RCA inputs of the amp. I didn't touch the amp in front of the console. This sounded good until some guy drove up next to me and I couldn't hear it anymore. Now I've upgraded. Boy, how I've upgraded. hope this helps,

Cadiken

theres a alot of room back by the factory sub in the yukon xls. I did a truck for the Salvation Army once and we installes a spare battery, 4 radios, a extra speaker, a mic, and a fuse panel just in back! It was quiet a site, then up front there was some more radios in the center console and a switch to choose between front or rear battery for the power.