If you went to 10ft/lb you would be safe, IMO. I have not used a torque wrench on intakes except on 390's[cork @front & rear] and 3.0 duratec[plastic manifolds].
I have removed & replaced the throttle body a few times to R&R the cam cover gasquet and have yet to replace the TB gasket. I just push it in place, and wiggle until I can feel it fit into the 'old spot or grooves' that it came from. Seems to be working ok... The bolts have a 12-pt head I think on my 85 at least, and I just happened to have a socket of the proper size that was also a 12 pt.
In short, these torque values are flat surface to flat surface with black paper gaskets that are not deformed too much by the installation. Head gaskets, in most cases, need to seal against a lot more pressure and coolant & oil passages, and additionally, take care of the expansion of the head & block from temp. These are pretty much the same, flat, with very low pressure differential so are not as touchy.
tom