Welcome and good luck with the build. Others have posted some pretty solid advice, so I won't repeat, but instead will try a few other offerings. First, plan to be able fit gear for 4 people because as your kid gets older, sooner or later he'll want to bring a friend along. Along with that will be an extra tent because kids with their friend will want/need their own sleeping space. Second, think about how you will ultimately use it. Trust me, this is likely to be an evolution. Mine went from dragging a PUP trailer to campgrounds and doing everything we could reach from the pavement, to venturing into dirt trails for the day and back to base camp, to fully mobile A-B-C no trailer and self-sufficient for longer durations with longer range. Third, I agree with building what you have, but I would start with addressing the weak points of the platform first: tie rods, trans, brakes, yada yada yada - you get the idea. Fourth, do your homework before you buy, cut, or weld. Some of those things you can't easily undo - ask me how I know - and I have learned to fab what I can to get it how I want it, and also to save my money to get the best quality of whatever it is I'm after (I've wasted money on 4WP junk that looks good, but is actually meant for a mall crawler and absolutely falls apart after a few hundred miles of corrugated track (wow - I really just said that? I guess reading Tom Sheppard's Vehicle Expedition Guide stuck in my head), um I mean desert washboard.
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As for the comment about a snorkel, if you've ever been in the deserts of Southern California or Baja and encountered deep silt - then you know exactly why a snorkel is a good idea. It is most definitely not about the look - I had my snorkel for 6 months before I finally got the moxie to cut a hole in the fender and put it on - but I knew I had to. The catalyst for getting the snorkel was a really dicey experience in some seriously deep silt in Anza-Borrego on a trail that (unbeknownst to me) had been closed and removed from current maps (another lesson - buy current maps/guides) due to extremely deep silt. The other advantage is obviously water. When I first started modifying my truck, we were at what is the west end of the Mojave Road (didn't know it at the time) and there was a river crossing. Knowing where my air intake was - I backed away and did not cross it for fear of sucking water in the intake and hydrolocking the engine. Fast forward a few years, with a snorkel, we came across that same river from the opposite direction (completing the Mojave Road) and it was substantially higher than the first time we saw it. This time however, I had the confidence to drive right on through it. So, to each his own, but it is a functional item and should not be mistaken for anything other than that.
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Finally - Use It and Learn from it. One of the things that helped us was to make a list at the end of every day. We break the list into categories: Vehicle - how it rode and handled different types of terrain, any issues, fuel mileage/temp - etc; Gear - how it performed and how easy/difficult it was to access and use (also - what didn't we use, or needed but didn't have); Food/Water - amounts, stuff we liked and stuff we didn't - what we wanted more of and what could be left home. When we get back from a trip - within the week we begin executing the changes/ideas from the list while they are fresh in our minds.
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Have fun with it. Take a lot of pictures (we like pictures) - in time, when you look back at them, you'll be amazed at how much your rig will have evolved.