I have 3 cyclops tractors that I really enjoy using since I restored them. The plastic hood, grille and side panels are the nemesis of all the cyclops models. It is very hard to fix the panels, especially where screws/studs and pins are located.
As you may know, the plastic parts are costly to replace as well.
Perhaps you could try some 2 part epoxy to fill the holes and then re-drill and tap them to use machine type bolts. As I recall the grill hinge is held in place with coarse sheet metal type screws. If you fill the holes, then drill and tap them using short machine thread bolts, you will be less likely to mess up the plastic any worse than it is.
The 4 studs on the hood panel can be done the same way. Or you could try some superglue on these if the holes are not too bad. It is tedious to say the least to fix the plastic parts. Getting the hood to fit correctly is also a frustrating.
Good luck!