Hi Stert,
No need to cut up a good tank, can't you replicate the ears on a small plate where you drill 2 holes in to mount on to the tank, that's where these 2 screws/bolts are for. Or you can choose to mount a piece of steel 30x6(mm) on to your framerails with 2 silent blocks and let the tank sit on that. No need to weld, just use 2 U-bolts. Hope it's understandable, my english is not that great.
Cheers, Rob