Need to make an 8mm diameter hole in very tall hollow aluminum casing...any suggestions?

aluminum casing is about 5 meters tall, and 3 meters wide, need to make an 8mm hole near the top without damaging the rest of the casing. the walls of the casing aren't very thick, so i guess drilling is out of the question seeing as it would bend and possibly crack the aluminum....any other ideas that might work?Need to make an 8mm diameter hole in very tall hollow aluminum casing...any suggestions?
Unfortunately I doubt that this can be done because the drill will stray over the 5 meters. Even if the drill were ground very concentrically, I can't see it making a full 5 meters. Maybe you can weld ears on the outside of the casing?Need to make an 8mm diameter hole in very tall hollow aluminum casing...any suggestions?
If you are going to drill through the side near the top you can put the casing between two v-grooved clamps of a drill press vise. Mark the location with a center drill to make a clean non-slip starting hole. Then get a very sharp (new preferably) drill that is 8mm in diameter to make the through hole. Put it in contact with the casing, drop on cutting oil, and slowly lower the drill bit. You should see aluminum shavings coming off the bit smoothly. Keep drilling (backing off occasionally to brush off any chips) and keep pouring on coolant or cutting oil.





People do this all the time so it should not be a problem.
Assuming the first answer is wrong and you wish to go down through the thin wall and not sideways through the big area. I think you are going to have to go either primitive or exotic and I am not sure either one will work. The primitive would be the style of drill that was used for boring out gun barrels in the past. I believe these used a scraping action at the end of a stiff rod so that once the hole was started and the long rod was carefully aligned it would be very difficult for the bit to get out of line. A problem being that the bit has to be cleaned of chips often and on a gun boring rig, it can be backed out on a lathe bed, kept perfectly in line, and this would be much harder with the large casting requiring a precise jig.


The exotic would be to use some kind of electrode reaction on the end of rotating hollow tube so that removed material was evacuated and the rotation kept it straight.
If you have access to a vertical milling machine I would prefer using a free cutting type tool, such as a 8mm diameter carbide 2-flute endmill. This works great if you are concerned with drill drift. At high rpms the cutting force that deforms the part is eliminated.