Progressive Industries Surge Protector Install Question

[BeerBrewer]

6 ga wire should be very close in size.....no matter what.

I thought so too, but that was not what I expeirenced. I think my issue was to the very fine stands of wire in the cable. They easily got "bushy", so I had to be extra carefull with them, but they did fit. The other issue was the ground in the original Romex was 10 ga solid copper and the gound in the that wire I used was 6 Ga stranded. This meant I had attach a use a crimp tool to attach a lug connection to ground wire and my wire crimper was too small, so I had to upgrade it.

The bottom line is that in my opinion, it was not worth effort and added cost.

[Casa_Woody]

I know the you already completed the work but so folks understand that all 6AWG cable is not the same.

Don't want this to turn into an NEC discussion/debate but just be aware:
Per NEC art 400: 6/4AWG (3-current carrying conductors and 1 used as ground) JOOW/SJOOW is rated at 45Amps, and the cable type is not permitted for use in this application
Per NEC art 310: 6/3AWG NM-B/Romex is rate at 55Amp, and is of the proper cable type for this application

I deviate from "procedures/regulations" all the time. I just attempt to fully understand the effects of doing so. I also have some 6AWG SJOOW in use on my AC input line.
Bottom line: I don't believe you are unsafe. I doubt you are pulling 45A per leg. Just wanted to make sure you and those reading this understand the requirements so an informed decision can be made.