Ork Warboss-cyborg body, mega armour, power claw, big shoota, boss pole.
Mega Armour comes with powerklaw and a shoota, so you don't have to take those. Unfortunately, you can't take the big shoota with mega armour, but you can upgrade the shoota that comes with the mega armour. I would go for a cheaper boss at this level, maybe just a cybork body, 'eavy armour, powerklaw, and choppa. He would also be much faster moving across the board.
26 sluggas boys- 30 choppas, 18 sluggas, 2 burnas.
7 have double close combat weapon, one has double slugga.
Each counts as having a choppa and a slugga, regardless of what they may actually have. Split into two mobs and max out the amount of burnas taken, they will be incredibly useful against necrons as power weapons.
13 shoota boys-12 shootas, 1 bg shoota.
Get 3 big shootas, even if you have to make the mob only 10 strong. I'd even pick up a nob with another big shoota for more firepower.
8 Stormboys- 10 choppas, 6 sluggas
two boys have double choppa
Too expensive at this level. I would simply ditch them all together.
8 truck boys- 8 choppas 8 sluggas
- 96 pts
Good, give them a burna boy and a nob with a powerklaw. Trukk has to take either a big shoota or a rokkit launcha. Against Necrons, I'd go with a big shoota.
For the most part, a very good list, especially for a newbie. Grab a squad of grots. This could be absolutely essential to victory, as they will shield you from necron firepower for a few turns.Also consider a Basilisk. Normally I'd say Leman Russ, but you don't want to get too close to necrons with vehicles, and Basilisk will make short work of them. Maybe ditch the wartrukk against Necrons as they won't have much support charging far ahead of your army. Grab a few more big shootas or maybe some lobbas aswell.
Aim for his warriors and concentrate all your firepower into them. Aim for a phase out. Good luck!