justcause2mods.com has lots of info on how to mod that stuff. it's fairly easy.
I'm using gibbed's tools right now. I don't see a reliable way to mod in infinite ammo. The only two infinite ammo mods I've found (other than of course bolopatch) were 1) specific to DLC guns and 2) one that lets you pick up as much ammo as you want but doesn't give guns 'infinite ammo'. And just a note, the DLC weapons files are a little different than the normal weapons files so I couldn't find a way to simply copy what the guy did to make the DLC guns have infinite ammo and apply it to normal guns. There's even a variable called 'unlimited ammo' for every gun, but changing it has no effect in game.
As a side note... changing your .exe to the old one (prepatch) will make bolopatch work again. However, it will mess up the changes from the patch (notably the fix for the prompts in eyefinity/surround). Of course, you can just go back to the /fovfactor fix, but I actually prefer a less zoomed out FOV after playing with the default FOV post-patch.
Another point of interest is that I've been looking for a file to mod to possibly change the HUD and center it while in tripe wide. If anyone else has any ideas let me know. So far I haven't really found anything of value in the archives.