1971-1973 Arctic Cat Snowmobiles Factory Service Manual, Page 42Get this manual
ENGINE SERVICING (TVVIN CYLINDER) 25Using lock washer and bolt, install the intake air shroud and the intake manifold, making sure that gasket is positioned on both sides of the air shroudTorque the six (6) bolts fromftlbsNOTE: If lock washers are not installed, bolts may bottom out and twist offThe two (2) longest bolts must be installed at the bottom of the intake manifold28Align the scribe mark made on the magneto assembly plate and on the crankcase and tighten screws securely
Now torque the cylinder head nuts to 16 ftlbs using the indicated crisscross sequenceNOTE: Insure the long nuts have been installed on PTa side of engineLoosen the intake manifold bolts and re-torque fromftlbs