I found this post, because I'm getting ready to install the same radio (Kenwood TM-V71A) into my 2016 GMC Sierra.
Did you connect both positive AND negative directly to the battery? If so, have you had any issues?
According to an article by Alan Applegate (K0BG) in the May 2015 issue of QST, as well as his website, he recommends NOT connecting the negative lead directly to the battery, because of the ELD (Electronic Load Detector). According to him, you should connect the negative wire to the transceiver to the common ground point, after the battery monitoring unit. I have not yet taken a look to see if my truck has such a thing, although I assume that it does. I'm planning to run power into the cab, with Anderson PowerPole connectors, so that later I can swap out the radio for something like an Icom IC-7100 if I want to add HF.
For instance, see: http://www.k0bg.com/wiring.html
Or check out the May 2015 issue of QST magazine from the ARRL archives. However, his website has much more detail than the short QST article.
Thanks, MojoTexas (N5MAJ)