2 choices, fit the bearing to pressure plate, tie the fork up out of your way, fit engine and fish the fork back down into the release bearing and push back in fork shaft....
Or i prefer to fit bearing onto the fork and onto the spiggot shaft, put shaft back in through the fork,
Fit the engine, push fork back towards bulhead, and when it comes against pressure plate , hit the fork a bang towards the bulkhead with a hammer to get bearing to clip into preesure plate
FFS turn the clutch plate the correct way around and dont forget putting release bearing in before you put engine to gearbox, as having to lift engine out agin is a bit of a bitch