A method of installing a valvetrain in an internal combustion engine comprising a cylinder head, a poppet valve having a seat within the cylinder head, a cam shaft on which is mounted an eccentrically shaped cam, an electromagnetic latch assembly comprising a latch pin translatable between a first position and a second position; and a rocker arm assembly abutting the poppet valve and comprising: a cam follower positioned to follow the cam; and a rocker arm forming a chamber out of which the latch pin extends when the latch pin is in one of the first and second positions; wherein one of the first and second latch pin positions provides a configuration in which the rocker arm assembly is operative to actuate the poppet valve in response to rotation of the cam shaft to produce a first valve lift profile; the other of the first and second latch pin positions provides a configuration in which the rocker arm assembly is operative to actuate the poppet valve in response to rotation of the cam shaft to produce a second valve lift profile, which is distinct from the first valve lift profile, or the poppet valve is deactivated; and a solenoid and two permanent magnets (120A, 120B) forming part of the electromagnetic latch assembly is mounted to the rocker arm; the method comprising: mounting an electromagnetic latch assembly to each of a plurality of rocker arms; forming a valve actuation module by attaching the plurality of rocker arms, corresponding hydraulic lash adjusters, and a wiring harness to a frame; and installing the valve actuation module on the cylinder head so that the rocker arm assemblies abut poppet valves and the hydraulic lash adjusters provide fulcrums for the rocker arms; installing connectors that make electrical connections between wires of wiring harness and wires of each solenoid, thereby facilitating installation of a valvetrain. a cylinder head, a poppet valve having a seat within the cylinder head, a cam shaft on which is mounted an eccentrically shaped cam, an electromagnetic latch assembly comprising a latch pin translatable between a first position and a second position; and a rocker arm assembly abutting the poppet valve and comprising: a cam follower positioned to follow the cam; and a rocker arm forming a chamber out of which the latch pin extends when the latch pin is in one of the first and second positions; a cam follower positioned to follow the cam; and a rocker arm forming a chamber out of which the latch pin extends when the latch pin is in one of the first and second positions; wherein one of the first and second latch pin positions provides a configuration in which the rocker arm assembly is operative to actuate the poppet valve in response to rotation of the cam shaft to produce a first valve lift profile; the other of the first and second latch pin positions provides a configuration in which the rocker arm assembly is operative to actuate the poppet valve in response to rotation of the cam shaft to produce a second valve lift profile, which is distinct from the first valve lift profile, or the poppet valve is deactivated; and a solenoid and two permanent magnets (120A, 120B) forming part of the electromagnetic latch assembly is mounted to the rocker arm; the method comprising: mounting an electromagnetic latch assembly to each of a plurality of rocker arms; forming a valve actuation module by attaching the plurality of rocker arms, corresponding hydraulic lash adjusters, and a wiring harness to a frame; and installing the valve actuation module on the cylinder head so that the rocker arm assemblies abut poppet valves and the hydraulic lash adjusters provide fulcrums for the rocker arms; installing connectors that make electrical connections between wires of wiring harness and wires of each solenoid, thereby facilitating installation of a valvetrain. mounting an electromagnetic latch assembly to each of a plurality of rocker arms; forming a valve actuation module by attaching the plurality of rocker arms, corresponding hydraulic lash adjusters, and a wiring harness to a frame; and installing the valve actuation module on the cylinder head so that the rocker arm assemblies abut poppet valves and the hydraulic lash adjusters provide fulcrums for the rocker arms; installing connectors that make electrical connections between wires of wiring harness and wires of each solenoid, thereby facilitating installation of a valvetrain.