Yeah its unlikely you over torque them.
Intakes can be hard to seal. I make a big job of it, I use that almost $40 gasket, clean the surfaces with brake cleaner--others like carb clean have oil base like. I hi-tack the intake gasket to the head only and keep the intake side dry--those gaskets are re-usable if done right. The gaskets stick to the heads and stay put forever until you throw them away.
Tightening the intake is a biggie, no room for torque wenches either. Its a feel you get, start in the middle and first snug them all up and work in small steps. Very surprising how long it takes. You think its tight and when you get back to the center you see its loose again. I aim for around 25-30 lbs only by feel.
Taking the intake off will tell you alot, be sure to drain the rad first.