Upgrade PCIe or add SATA ssd to Mac Mine late 2014?

Background (and confession):

I have a 2012 Mini which I upgraded in 2021 with the Mac Mini Unibody 1TB SSD Upgrade Kit. Because that Mini's OS is no longer update-able, I just bought a used late 2014 Mac Mini 3.0 i7 with a 256 SSD. I thought I'd just swap the SSDs--puting the SATA 1TB from the 2012 in the new one, but I clearly didn't do my homework well. When I got the 2014 apart, I realized the SSD is PCIe (of course, you're thinking, right?), so it won't go in the 2012 to swap. And when I tried to put the 1TB SSD in the bottom section of the drive carrier, it's cable won't reach the connector.

I need at least 1TB on the new machine, since it's the main computer for household files, photos, music (all backed up, in cloud and external) I've read numerous discussions that my options are to 1) simply upgrade the PCIe (the most expensive option) using a 1TB OWC Aura Pro x2 SSD, or 2) a dual drive option, leaving the 256 blade in and adding a SATA drive below it in the underside of the carrier (I have both the 1TB SSD from the 2012 kit, and the original SATA HD, currently in the IFixit external case as a TimeMachine disc).

My questions:

1) Which option would you recommend? And in the case of option 2, what's the best config? And does it matter much if I use the SATA HD or SSD?

2) As mentioned above, the drive cable currently on the SSD SATA doesn't reach the connector on the 2014 logic board. Is this the one I need to do that?

3) I don't have the parts (grommets and screws) necessary to mount the SATA drive securely to the carrier if I go that route. Can you direct me to where I can find those? iFixit seems to only have them in a Dual Drive Kit for the 2011 and 2012, along with tools I already have.

Grateful, in advance, for any help you can offer.