Yeah, you can do it, but most guys with a little experience consider in-car to be a total pain in the ***.
Rod bearings aren't badm just some crank rotating for position and unbolt rod, remove cap, push rod of journal enough to get upper half bearing out, replace both bearing sections and reassemble in reverse of disassembly.
but the mains, a trickier deal, since you need to have all five caps loose and drop the crank down a hair to be able to get upper main bearing halves rolled out.
One tip is to use a low headed common wood nail slid into the oil feed hole in the crank to use as a means to lever the upper half bearing out as you rotate the crank....head of nail hooks one edge and pushes the bearing out as crank is turned.
Then you've got to hope you can get the split rar main seal to seal up, that the timing cover seal is still good and that you can get a good seal on the pan gasket in-car.
I find it a bunch easier to just pull the motor and do it on the engine stand....you trade unhooking a bit more stuff and time pulling the engine for a lot less frustration, cussing, and hair pulling under the car. Plus you can make sure everything gets sealed up properly.