Thanks, Mike. Yes, it is a standard MS3509 aircraft battery connector, rated for 750 amps continuous- 1500 amps intermittent. Overkill, but I had one so I used it.
I found a nice Clark Cable crimping tool on eBay for the wire terminations that I'll be doing soon. I lucked out on it-- incredibly cheap for this type of tool. These put a proper crimp on terminals made by AMP, T & B, Molex, etc. I'm avoiding those Chinese- made crimp terminals because they are not reliable.
Regards, Neil Tucson, AZ