Old post, but still found in a search, and no answer posted yet, so...
According to "man nvidia-installer"
Install a kernel module only, and do not uninstall the existing driver.
This is intended to be used to install kernel modules for additional ker-
nels (in cases where you might boot between several different kernels). To
use this option, you must already have a driver installed, and the version
of the installed driver must match the version of this kernel module.
And you can also follow these 5 steps to have modules in multiple kernels,
I believe irrespective of driver version:
1. Boot with the new kernel.
2. Then cd to the following directory : /lib/modules/OLDKERNELVERSION/kernel/drivers/video/
(replace OLDKERNELVERSION with your own specific version)
3. Make a copy of the old driver: "cp nvidia.(k)o nvidia.(k)o.old"
4. Run the Nvidia installer
(this will create the new driver in /lib/modules/CURRENTKERNELVERSION/kernel/drivers/video/)
5. In the same directory mentioned under 2 do a rename to the original name
"mv nvidia.(k)o.old nvidia.(k)o"