Well, as promised ill try my hand at this with the intention of getting my work flow much better and generally picking up new ways of doing things.
In this case I put EQs mini tutorial on how to make the holes into this one by cutting the quads out and making the hole out of a cylinder rather than boolean and cleanup, which is how i would normally do it,still not sure which one i prefer. but EQs method does mean the exterior mesh rings are consistent,as apposed to cut by hand which is how i normally do them if they are mesh smoothed.
Ill delete those lines near the bottom on the flat face, I was experimenting this theory of EQ.
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The other thing I find difficult,which maybe due to my extensive use of loops/rings and making them flow to the edges is keeping things nicely aligned and lined up...i.e keeping a flat surface acturally flat on the mesh...keeping lines at the correct angles as I build and extend etc.
Anyway nuff chatter heres the .obj :-
http://hedgeart.net/uploads/Bronco_week01_part01.obj
Image:-
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