Step 5 : Redo most steps for engine cover. Be careful to ensure tangency at the seam for aesthetic purpose.
Cab8.jpg
Step 6 : Use mirror function (though for printing I think it would be a nice place to divide the model)
Cab9.jpg
Step 7 : Do a thick shell
Cab10.jpg
Step 8 : Prepare the front lights with a profile
Cab11.jpg