I think the chassis is 'modifiable' depending on load, just as you see the Gíthúrai buses whose chassis is Isuzu FRR appearing unusually long. I've come across some rather long Fuso Fighters by the way, complete with an extra axle that makes them 'miguu kumi'.
Basically, maisha yake inakuwa rahisi kuliko ya 844. What I've observed is parents move their B- grade kids to IG to make them A- grade kids. It's an easier system to succeed in exams ikiwa umezoea kusukumwa ya 844.