Trackmaster (flat drive unit) Hunslet Austerity shell

I had a Hornby J94 in the United Steel Works liver, turned into an OC, but then thought "I should make a Trackmaster version just in case if I want to record something" because at the time, I had more TOMY Trackmaster and Trackmaster 2.0 track. with minor modifications of the 2012 Percy chassis (the chassis with the flat type drive unit and says 2009 for some reason underneath) you can make your own Austerity/J94

UPDATE: I should've mentioned it needed to be slightly modified to allow the wheels to have clearance, now only a smaller portion needs to be removed

UPDATE 2: new file that should allow the tab to be used, also the measurements when printing should be 110 mm, 39 mm, 32 mm. I wasn't aware that the file isn't compatible with other printers

UPDATE 3: changed to an updated file that should hopefully work better than before with other printers

UPDATE 4: modified the design slightly to allow better access to the activation switch and included whistle and safety valve, o