Can anybody tell me if the gauges on the info page are user definable? Can I set up the unit with the gauges I want or is there a predetermined gauge panel that cannot be changed?

There are several styles of info gauge pages to select from.  Yes, each of those pages and gauges can be edited to show whatever avaliable data you want.

Ordered the Lowrance to Yamaha cable and the NEMA starter kit off Ebay.  Going to remove all gauges from the dash on my Stroker and use the info page on my HDS unit for everything