I need to fill a set of holes on my throttle boddies and wasn't sure the best way to do it. I have the holes from the front set of butterflies and possibly the holes from the injectors (assuming I use the car injecters (see privous posts for any advice on that issue)).

Can I use araldite or the like?

Araldite is resistant to petrol so should be OK although I would be inclined to use JBweld of some kind of chemical metal.
I would also chamfer the outside of the holes just to ensure the plug doesn't go inwards if it ever comes loose.