I've never heard of that alternator brand. I would be leary of
Amazon and
eBay for alternators. Cheap ones advertise higher output, but you have to be at a high engine RPM to realize it. Basically, the output is unusable. They also tend to have questionable diodes/rectifiers/etc. These cheap alternators frequently put out less current than your factory alt at idle.
What you need to look for is high idle output. Good brands optimize the design balancing all factors to work will within the physical size of your alternators case. To go beyond this, you have to use a large-case alternator which will require custom brackets (fairly expensive) and may or may not be possible to physically mount in your vehicle.
Depending on the alt, it may have a smaller pulley which may require you to also buy a ~1/2” shorter belt. Oftentimes, on vehicles where multiple amperage options are offered, the smallest option will work with the factory belt and the largest will require a shorter belt.
Btw, I originally recommended knu konceptz bc that's what I personally use, and the reason I mentioned their 4/0 is because they do not offer a size in between this and 0 gauge. I personally would rather use one large run than multiple smaller runs. For lesser installs, I use the Recoil OFC kits bc I'm affiliated with them and an authorized dealer. Knu is reasonably priced for being high quality and they also offer a convenient one-stop shop for RCAs, distribution blocks, fuse holders, speaker wire, accessories, etc.
Welding cable is always cheaper, but you do need to consider that Knu or Sky High 0 gauge cable is oversized and is the same as 1 size bigger in welding cable. The important thing here is to just not buy really cheap wire bc it frequently is undersized and will just have a really thick jacket. Also, a lot of the high quality car audio cable is tinned - they do this for corrosion resistance - I wouldn't be too concerned about this feature. It certainly can't hurt, but it's not worth paying extra for. I've never seen high quality OFC wire of proper size fail in 20 years.
Just avoid CCA wire. You can cut certain corners in car audio, but wire is not one of them. I've had numerous people come to me with amps going into protect or even blowing due to inadequate electrical. It never fails to amaze me how some people will buy a Taramps HD3000 and then use 4 gauge CCA wire on factory electrical and then wonder why their amp blew!
In my present personal setup, the single highest expense was wiring. Of course, I test out a fair amount of gear, so I wanted to be able to quickly switch/add things easily.
The point is... running wire is a pain, and you don't want to have to do it again later. I know you said you won't upgrade, but experience has shown me that the type of person doing more than the basic subwoofer addition or factory speaker swap is likely to upgrade many times.
The only thing worse than wire is sound dampening treatment. I recommend ResoNix products for this area, if you're interested. 2 hccas on that amp will make you hear rattles you never knew existed lol. It's not cheap, but it's by far the best quality and performance. I use the CLD and the foam speaker rings in my personal vehicle.
The posts are accurate about running an additional ground to the battery. I never have anyone do this for basic installs, although I do strongly encourage people to use a ground block instead of running multiple grounds for different amps. Of course, if you have a secondary battery, I recommend grounding to that battery negative and then grounding to the chassis from the battery negative with a large gauge. The ground block is optional in this scenario - sometimes it's cheaper and/or easier to just use separate runs to the battery.
Make sure you build a sturdy amp rack and that you build a proper box for those subs. I haven't really ever heard a bad sub, but I've heard a plethora of poor enclosures. You'll definitely want a double baffle and adequate bracing for subs of that magnitude, along with adequate port area and proper tuning frequency.