Ok, so that's MOS 5 for the Heat Sink install: 10 minutes
MOS 2 for the SRM-4 Removal: 100 minutes
MOS 1 for the first Laser: 110 minutes
and MOS 2 for the second, +1 for the previous roll: 90 minutes
With the 20 minutes for the ammo bin removal, that's 330 minutes of Engineering work overall. Not bad!