Breaching the upper floor of a landing ship

[Cynical 10]

So, I just lost my fourth campaign to a wipe on the exact same UFO layout, and I really need help before I'm willing to spend another 10 hours to wipe in the exact same spot a fifth time.

How the heck are you supposed to breach the upper floor of a landing ship if it's got Sebelians or Androns?  It seems 100% impossible; I've tried everything, and nothing works.  Blowing the doors open to not get pot-shotted is easy, but they just stay out of LoS of open doors; you have to run in.  Shields don't help, because you're running into an open room and taking fire from lots of different angles.  Grenades don't work; Sebelians at that point are too tough for stun grenades, and Alenium grenades don't do enough damage to even scratch them.  Rushing doesn't work; you simply don't have enough DPS to get through Andron's health/Sebelian's HP regeneration.  Trying to pot-shot from around corners doesn't work, even if you can do it without getting interrupted, they'll just regenerate any damage you can do.  Suppression doesn't work; it never procs on these guys, and it's not like you're going to try to do a mission with nothing but machine guns anyways, so you'd never be able to suppress all of them.  I'm completely out of ideas; it seems like once you start downing landing ships the game effectively ends, there's no way into that upper-level cockpit without wiping and losing four months worth of Workshop time on Armor/Weapons, which is a completely unrecoverable situation.

[Edmon 3]

Press "R" for Rocket Launcher

[Cynical 10]

I actually tried Rocket Launcher on attempt #4; that was part of how I lost six guys on one turn and ended up wiping (seriously, how do you miss your target by 30 degrees?!?!)

I've gotten to March 1980 on attempt #5, and think I've found something that's working -- I've stopped using assault rifles entirely, and instead run this:

2x Shield + Pistol or Shield + cattle prod

2x Sniper rifle with Shotgun in the backpack

2x machine gun

2x Rocket Launcher

 

Start the mission with a basic UFO approach with shield acting as scout, sniper + machine acting as fire support, Rockets acting as cover destroyer (and also destroying the front door of the UFO).  Usually during the "approach" phase of things I'll break into two four-man fireteams that stay close enough to offer each other support when needed.  When it comes time to push in, have snipers switch to shotguns, and abuse the combination of teleporters, the low AP costs of pistols and shotguns, and reaction modifiers to just potshot like crazy.