240 Rad on the front would be no problem, the position of the 140 fan might might make it a tight fit with the motherboard and any large caps, would need a slim fan for sure.
I'm away from home at the moment but will give a measurement soon as Im home Wednesday.
I'd forget the 140mm,it's too tight.
2x120mm Ek coolstream rads will go in the front on their sides with the drive bays gone and some Optical drive bay trimming.(these are the only 120mm rads you can do this with in this case)
You can still use the optical drive bay doing it this way,if you go for a straight up 240mm rad you lose the the whole bay.
Doing this allowed me to install a Lian-li EX-533b and use a slimline optical bluray drive with a 3.5" drive sat underneath it.
My ssd is using one of the mounts in the floor of the case.
If you still want more rad power the best option is to use another 120mm in the rear fan mount,you'd have to drill more holes further into the case to get the rad mounted further in and allow the case side to go back on.
In all honesty with SB setups running so cool 2 rads is overkill anyhoo,you could get similar temps with a H60/H70 and save yourself a load of hassle.