55.2-59 Under bed fuel tank help

[Missyblue]

Hi this is just the start of an idea but I'm hoping for advice.
To mount fuel tank I know most people move the crossmember between the shackle mounts to the back. But could I cut and leave the top portion like in number 1.

My shock crossmember is broken. Would you repair or remove? I have a 70s axle and it actually has shock mounts on the cab side so maybe fab a mount and crossmember on the cab side?

The other photos I like how they added the metal tubing to make mounts for the tank. This is the exact tank I am using. A 87 blazer rank baffled for efi so I can use my stock fuel.pump and sender like my 91 engine ran. The green would be places to add square tubing supports...

Any ideas and tips appreciated. Thank you