95 Toyota Avalon receiver and amp wiring

I was wondering if there is anyone out there who actually has an Avalon and has installed a head unit, and if so how you went about it exactly.  I was also wondering how much power the factory amp in an avalon has.  And my last question is about amps themselves.  If you have a receiver that has 70 peak watts 60 rms and you have to go through an amp, say a factory one that may produce less power than your receiver, would it be better to bypass it all together and connect directly to the speakers or run through it anyway.  What I'm basically asking is if  when an amp inside a receiver is wired to another amp do the two powers add up or do the speakers they're connected to only feel the power of the amp?

I dont have an avolon but I would probally just run new wires unless there is a simple by pass kit. Also no deck on the market prodeces 70 watts max 60 watts rms. Not unless that 60 watts rms is the total power of all 4 channels combined.double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

beat me to it... just get the metra part. it's easy

Ravendarat wrote: I dont have an avolon but I would probally just run new wires unless there is a simple by pass kit. Also no deck on the market prodeces 70 watts max 60 watts rms. Not unless that 60 watts rms is the total power of all 4 channels combined.

Panasonic jsut came out with a new HU that "Claims" 70 x 4 peak and 60 x 4 rms.  Its called Panasonic MXE-CQ-c9800u, and thanks everyone for your help.