Got a new mod installed this week.
Here's a pic of what I started with...
Here's what I ended up with...
It's the Rugged Ridge dual battery tray, and I'm running a pair of Autozone Gold series batteries. My old battery never failed me at all, but with a winch, a lot of lights, and my tendency to wheel alone, I wanted a little extra oomph for all those accessories. It also helps that I had $50 in Autozone gift cards, $120 worth of credit on my Autozone account, and a coupon for $20 off $100. I got both batteries for $50 w/o turning in my old one.
So basically...dual batteries for less than $200 with the tray, batteries, and wiring! That's hard to beat I think!
As you might notice in the picture, I didn't run a relay or disconnect between the two batteries. I just wired them in parallel and called it good for now. Eventually I may get around to doing something different, but for now I think this setup will work well for me.
As for the tray...well...the instructions leave a lot to be desired, and either my Jeep is a little tweaked (Certainly possible at its age), or their bracketry isn't quite correct. After a little work w/ the hammer I was able to get all the holes to line up and everything tightened down. I will say that it's extremely nice that the tray kit came with a bracket for the relays and such. You can see them mounted on the front left corner of the tray. I'm very, very happy about how cleanly they mount to the new tray. Things I didn't like so much...having to hang the ignition coil by one bolt rather than two because it interfered with my new batteries and having to relocate some other stuff w/o having clear instructions. That said, the ignition coil relocation may be due to my battery choice. The stock batteries are much, much smaller than the ones I chose. I did a bunch of measuring, looked up sizes of batteries on Autozone's site, and then went to Autozone with the tray and did a test fit. These batteries barely fit, and I'm only running two hooks to mount them rather than the three that the tray came w/ since there's not room between them. Perhaps with two stock size batteries (which are smaller in every dimension) the ignition coil would not need to be rotated slightly.
Anyways...this is a rambling but I wanted to include details of my experience since I couldn't find ANYTHING online about someone else installing this tray in an early YJ. If anyone has any questions about the it, feel free to ask.