how many channels?

I'm assuming the upstage kit just attaches to the 61 components via their crossovers.  If this assumption is correct these will comprise 2 channels. 

So you need 6 channels amplified. 

1)  upstage + components
2)  dash speakers
3)  rear speakers

Remember you can use power from the head unit to power one or two channels, if necessary.

I'm not sure who you consulted about the cl-4x dash speakers but with your highly rated components and upstage tweeters those dash speakers are a horrible idea in my opinion.  They'll totally ruin the delicate balance that the upstage tweeters are designed to obtain, create bad sounding harsh highs reflecting off the dash, and possibly cancel out some frequencies from either the upstage or the components. 

My advice is to take them back.  I think your setup will sound much better without the dash speakers if you're interested in sound quality.  If you're just interested in making it loud, then keep them in.

grnxb:

It sounds like all you'll need is the two channels if the crossovers that come with the cl-61and upstage tweeters play together (again, I'm making an assumption here, you might want to check this out).

In that case I would highly recommend you find some sort of amplifier for these, even if it is a less than permanent solution.  Those head units (all head units really) put out less than 20w rms and it usually isn't very clean power.  I'm afraid it would be a shame to hook your fairly expensive speakers to that power.

You can find cheap amps from decent brands all over the internet.  I would seriously consider this:  https://www.cardomain.com/item/XTA403A

It is a very high quality 3 channel amplifier.  You can use the 3rd channel to power a sub in the future and can save yourself some money by not going the powered route.

Look for closeout deals like this.  You'll find them all over the internet and ebay.  The warranty might not always be the best, but I was in your shoes when I upgraded my amps a few months ago, and found my amplifiers online for less than $200 each.  They work great.

Check out brands like Memphis, Diamond, Xtant, Audison, Zapco, Eclipse, Arc, Alpine, Nakamichi for high sound quality.

Your best bet is to go with the crossover with a 2 channel amp. And if you can't seem to have it operating, take it to a local shop. Some of what theeset sounds like all you'll need is the two chan for the advice about the cl-4x's.  I just bought them to replace the stock speakers in the dash and didn't consider all of the additional speakers .(they will be on their way back to store)  I am probably going to disconnect the 4" dash speakers, and the speakers in the rear hatch area and run the upstage kit/door components off of two channels (one per side right?) and forgo the amp/powered sub until wife stops yelling at me about money.  The pinels if the crossoers that come with the cl-61and upstage tweeters play together (again, I'm making an assumption here, you might want to check this out).In that case I would highly recommend you find some sort of amplifier for these, even if it is a less than permanent solution.  Those head units (all head units really) put out less than 20w rms and it usually isn't very clean power.  I'm afraid it would be a shame to hook your fairly expensive speakers to that power. You can find cheap amps from decent brands all over the internet.  I would seriously consider this:  https://www.cardomain.com/item/XTA403A=It is a very high quality 3 channel amplifier.  You can use the 3rd chajust ordered the amp and it will probably be here before the sound deadening arrives.  thanks for all your help.  by the way, i will likely build my own box and will mount it under the driver or passenger seat to save room, know any good small sq subs (8", or ?) that do well with small enclosure (about . 44 internal cu ft) ?The space under the seat measures 5.5" tall X " 18" deep X 13" wide, and I was going to go with the little Kenwood wOOx self-powered nnel to power a sub in the future and can save yourself some money by not going the powered route. Look for =I'm assuming the upstage kit just attaches to the 61 components via their crossovers.  If this assumption is correct these will comprise 2 channels.  So you need 6 channels amplified.  1)  upstage + component2)  dash speakers
3)  rear speakersRemember you can use power from the head unit to power one or two channels, if necessary. m not sure who you consulted about the cl-4x dash speakers but with your highly rated components and upstage tweeters those dash speakers are a horrible idea in my opinion.  They'll totally ruin the delicate balance that the upstage tweeters are designed to obtain, create bad sounding harsh highs reflecting off the dash, and possibly cancel out some frequencies from either the upstage or the components.  My advice is to take them back.  I think your setup will sound much better without the dash speakers if you're interested in sound quality.  If you're just interested in making it loud, then keep them in. closeout deals like this.  You'll find them all over the internet and ebay.  The warranty might not always be the best, but I was in your shoes when I upgraded my amps a few months ago, and found my amplifiers online for less than $200 each.  They work great.Check out brands like Memphis, Diamond, Xtant, Audison, Zapco, Eclipse, Arc, Alpine, Nakamichi for high sound quality.

Good LuCk on your Project bro. Let me know if you need any help

I have no experience with shallow mount subwoofers. 

Anyone have shallow mount subwoofer suggestions for him?