I know this thread is kinda dead but I was looking for a custombackup.xml that was like this for a while, so I thought I would post it. There is a chance someone is looking for one that replaces LSPDFR backup. ie: just the basics such as police, sheriff and state. You just have to change the vehicle lines to the name of your own mods.
Local Patrol Los Santos: Police
Local Patrol Both Counties: Sheriff
Local Swat Everywhere: Swat ped I have in unmarked cars. ( I do not use Noose, I just use Local Swat as in LSPDFR barely any situations calls for a slow ass riot van/tactical vehicle.)
State Patrol Everywhere: Both regular and motorbike officers.
Noose Patrol: Do not used but lines are there for you to change. (My Local Swat is what I use when I need tactical units)
Local Air: Normal Police helicopter with unarmed pilots
Noose Air: Annihilator with no vehicle weapons but with armed swat units that will shoot their weapons.