It's very late for me, so I'll be brief. But you must remove the front mount from the shutter, it is in two parts threaded together, and locates the front two lens pieces in position. It should easily unscrew if needed, being a Va there may even be two very small holes for a lens spanner but these are not generally needed. Once the front cells are correctly installed in their mount assuming the rear cell is in satisfactory order the front mount should be fastened back into the shutter all the way until moderately firm. You'll then need to check the infinity adjustment of the taking lens with a ground glass and loupe, and correct it, if needed, before you consider adjusting the viewing lens, which should always be done last.
There are more detailed comments about calibrating focus of a Rolleicord on this site—I've written some of them—so do a search for relevant posts for elaboration on the above.