You can't use a bigger SSD if you stay with the fusion setup. Fusion SSD drive is limited to 128GB for some reason. If you use them as separate drives you should be able to.

I believe that the second fan goes in the empty slot (on the 667 model) next to the DC in port.

Antenna cables just pop off - straight up.

Must be perfectly aligned when reconnecting as well before you re-seat them.

Small needle nose pliers may be useful or a spudger or flat jewelers screwdriver to pry up on the cable as close to the connector as possible.

https://www.youtube.com/watch?v=NGwPcHDH...

I always make my own IDE drives from an 1.8" mSATA SSD and a mSATA/IDE case. Has always worked great in everything from the G3 Pismo on up.

https://www.ebay.com/itm/151519954907

https://www.ebay.com/itm/185391110542

You should have installed the OWC inline thermal sensor.

MacFans is the only other solution.

https://eshop.macsales.com/item/OWC/DIDI...

All you need to do to remove the GPU card and heat sink are:

1-Unplug the heat sensor (plugs straight in - on the back of the motherboard opposite the LCD heat sensor).

2-Remove the screw that holds the heat sensor to the frame in the upper right corner.

3- Remove the three screws holding the GPU to the MB.

4-Unplug the GPU from the motherboard.