Assembly should be pretty easy. I think I'll just go left to right dropping pieces into the dados on the bottom -> pop the top on. Until it's screwed / glued together there is enough wiggle room it'll go together fine. The top on the Othorn with the dados was a bit more challenging with all the internal pieces that you couldn't reach. With this one between the hatches, the ports, and the throat it should be easy to get the top lined up.
My friend took the Othorn I built with him to California along with the one he built when I did my Gjallarhorns. I had it for a few months but no longer. We were planning to build four more Othorns but then this popped up. Probably end up with 3-4 of the SKhorns instead between us.
@Ricci - Samps noticed that the hornresp you posted for the SW152's dropped off quite a bit higher than your original post. Is that just the difference between the SW152 and the IPALs or is something else at play?