How low will it be??

[Benny-]

So iIve got some Firestone 2600 bags laying around and I'd like to bag the rear of my truck for a lower stance that will still be able to two/haul. I'd like to run 2.5 drop spindles in the front and lower the rear 4 inches or so.

Question is, i have been planning on drilling holes in the frame and mounting the bag directly and running with schrader valves, but now I'm worrying that may be too low. If i can do it this way without mounting brackets that'd be great. If not i don't mind getting some brackets. How low will ride height be with the bags mounted straight to the frame? too low for only lower the front 2.5-3"?

Thanks!