Efi live is what you need to tune it and have a good tuner make u a few maps. Idaho rob, nick at duramax tuner (who is bata testing efi live for the 13s) just to name a couple.
Usually I'd say ditch all the emissions but on a brand new truck with a warranty I don't know if you want to do that.
Keep the tire pressures up and as others have said, check the fluid levels.
I'd add gauges (edge insight) just because the oem aren't exactly accurate.
UWUA AFL-CIO Local 1-2
'liLLY' 05 duramax 2500 CCSB 4X4- 334,995
Limitless Diesel Built trans with Suncoast 1054 converter
, Grade C's, ARP head studs, PPE Standard, Edge insight cts w/ EGT probe, Duramax Tuner race valve (plug), Magnaflow 3" downpipe, 5" flow pro, 265 transforce, Bilstein 4600, pcv rerouted, egr blocked, unplugged & bypassed, kitty delete, AFE turbo inlet, Reese wd/ anti sway hitch (cam style with trunion bars), Pacbrake airbags, 110 gallon aux fuel tank, Merchant 'all on' module, transfer case rebuilt (merchant delux bearing kit, pump rub kit and case half), home made winter front, duraflap front and rear, new rockers with bed liner