I'm back, building a new bike

As life goes, life gets in the way of things like, oh, blogging. And in the case of THIS blog, which is about family cycling, if we aren't out riding, there isn't anything to write about.
Until now.
This is a new/old build I'm doing for my 12yo who has outgrown his Haro mini. It's based on a mid '90's vintage Trek 820. For a very short time, Trek was actually making these in the USA! My wife has one in blue from the same year. Nice cro-mo frames, nothing fancy, just a simple mountain bike like no one makes anymore.
It's going to be singlespeed, using a wheelset I built many years ago. The rear hub is a vintage Shimano BMX freehub (the freewheel mechanism is part of the hub, like modern hubs, but uses a Sturmey-Archer style cog). The rims are narrow double wall, forget what brand.
I ordered some Shimano linear pull brakes and a Shimano crank too. The handlebar will be a vintage Hyperlite I was using most recently on my Surly.
Chain tension will be by a Surly thingy.
Cool thing about this, with a rear wheel swap I can have a geared mountain bike, but I think this will be fun for now.