Cutting the shroud can possibly lead to some cooling issues. The shroud is a VERY important part of the coling system. If you take the fan shroud off completly you would loose about 40% of the fans cooling potential. By cutting the fan shroud you will not loose as much but you will loose some of it's capacity. If you do install a body lift I would recomend once it on to see if you can shift the shroud down verses cutting it or possibly using some aluminum sheet and make a filler peice where there is a gap and a new lip where you had to cut the shoud off.
Personaly I'm not a big fan of body lifts and this is one of the reasons. The other reason is if you do alot of off roading the lift can exert extra stress on the cab mounts. Issues with clearence on the shift linkages and wiring is another.
Yes a body lift is cheaper than a spring lift but with a spring lift you gain so much more. Most lifts if you choose the softer springs will actully improve the ride over stock. Most of the soft lifts also dramaticly improve the articulation of the suspension.
Yes there are instances when a body lift is needed. Using say the doubler is one instance because you have to get clearance on the tunnel. But they only reguire 1-2 inches. Personaly 1-2 inches is all I would ever put on my truck for ANY reason.
Since you didn't take the time to tell us what size tires your trying to clear I can't make any other recomendations.
Diging it in the dirt with my K5's
Grim-Reaper