cwf150

Let me start out by saying i have a 2010 supercrew 4x4 with the fact Nav and Sync. I want to add the Mtx req so i can amp some 10's and throw an amp on some new comps for the front doors. I have a fairly good understand of basic car audio and have done it on my previous trucks. I am just alittle confused on how to keep the sync voice. I know it only comes through the front speakers but if i amp them will i loose the voice for sync/nav. Do you install the Req just like i would an LOC. The way i have done it in the past was just splice into the rear speakers behind the dash. Run wire back to the REq then run speaker wire from my amp to the factory speaker wires behind the dash. Since i have the Sony system in my truck do i need to take all of it out. i hear that there is an amp under my console as well as the one on my fact sub. I know i will be removing the one with the sub but what about the one under the console. Could someone please tell me what would be the best way to wire in the REq and keep the sync voice. i would rather work with the wiring behind the dash since i can keeo track of the wires better. Thanks in advance.