Looks nice! How is the balance on it if you lean back?
I haven't leaned back on it too hard. I bolted the plywood to the chair, then balanced the chair on the base to make some drill spots. I didn't check it too thoroughly since getting it not to tip over was more like 3/4 of the way forward. I pushed it all the way forward and it didn't seem like it was off balanced, so that's where I marked. But there's not much need to lean back on it since the seat still has the OEM recline function.