[Msquared]

I agree with SW Rocket on this. I'm sure he knows much more about these things than I do, but we're on the same page. I can't see any way that the AF speakers are going to be tolerable (much less enjoyable) as drop-in replacements for the Bose junk. The volume/impedance situation is one thing, but the funky EQ stuff that they do to make $0.99 speakers sound decent is quite another.

If you didn't want to spring for the Helix 6ch amp right now, you could literally get any cheap (even used) 4-channel amp ($100 or less if you shop FB Marketplace) and use it to power the four AF speakers for now. In that scenario, I think you can use the Axxess controls to set EQ, delays, and filters (SWR, check me on that please). Site the amp anywhere in the trunk you want, the battery is also back there with easy-to-connect positive posts on the block next to it. It's not hard at all to run speedwire from the passenger footwell to the trunk and back for the when you're plugging in the Axxess: just pull the sill plate and the back seat bottom (5 minutes) and run the cables under the sill plate. To plug the Axxess in to the radio module, you probably don't have to pull the whole module out: I was able to plug my breakout harness into it by just removing the bottom multi-function bracket from the bottom of the dash above the passenger footwell, and then I could see and reach the plugs on the radio module that I needed. We can give more details on this when you're ready.

Then you could upgrade to the Helix later, and it would essentially drop in where the cheap interim amp is. You could also do the sub and 1ch Helix at that time, or put it off even longer. The advantage here is that you get three significant upgrade steps, and each one will give you real sonic upgrades that will be very noticeable (gratifying). The speakers are the hardest part either way. The GS25 and 690 play amazingly well even on the 50wpc of my little Kicker Key 200.4 amp. They will play a true 40hz and they are very efficient. People underestimate how low 40hz really is, because they almost never hear it (OE systems don't play that low, and neither do most home stereo systems). Depending on what you want from your stereo, you might even decide you don't need a sub.