Now after studying the pictures I can see that this printed kit is an M14 anti aircraft halftrack body, as can be seen by the fold down armor along the top. Much like the M16 this allowed the guns to rotate without hitting the sides once folded down.
While both M5 and M9 International Harvester half tracks weren’t any longer than their White/Autocar/Diamond T counterparts, the IH M14 was longer, so that explains it.
