Oh. I redid the first area and got through with no damage, so the second area doesn't seem as impossible now. Still having trouble with it, though.
It's not really bad. Just use a stun grenade on the first crowd. Then use your Mk.2 for the next enemies (important than you stun the gunner and then get the one on the truck).
Next up is another group. Get the 2 gunners asap using Mk.2, the rest isn't that important.
Now for the slow-mo scene: switch to auto-aim mode, use solar gun and when slow-mo starts, press L1 till you get a lock, then hit R1, release L1 and press it again as fast as possible, wait a tick, then press R1 and repeat. If you do this right, you will stun EVERY enemy till you land. And the rest should be piece of cake. Don't use the solar gun that much, especially for first and second part. You will need it a bit for the third part. And I also save a little bit more so that I can stun the beauty within a few seconds.
For the third part, you should know that the beast and its companions shoot, but will NOT HIT YOU at all. Which means leave them alone. The beast will take hits onto the boss fight, but it's not really worth it.
The first gunner - use auto-aim to stun him using Mk.2
The second gunner - DO NOT use auto-aim, it won't hit him. Use manual aim using Mk.2
The third and forth gunner (if I remember correctly, the gunner that will close in from left and right), try to manually aim using Mk.2 and hit at least the gunner on the left side. Auto-Aim won't work here as well.
After that another slow-mo part will happen with 2 jeeps. Don't use auto-aim. Don't even aim at the gunners, they won't hit you at all. Try to aim at the soldier right behind the jeeps on the left during the slow-mo with your Mk.2 (manual aim). If you are fast enough, you may also hit the soldier on the right afterwards.
And from this point on, use auto-aim and the solar gun, which makes it really easy.
Driving down the stairs - well, you can do that using stun grenades or by using solar gun as well. Depends on how good you are with the grenades.
edit; jimi_dini, I wish you had posted that an hour and twenty minutes ago
. A very useful tip, do you know how long so I can add it to the OP?
Don't know exactly. Maybe even 1-2 weeks. Didn't use it this time at all.