So for those who may have to do the same job.
1) removing flywheel, having a flywheel remover itís a doddle. Without one itís a pain and I had to make, with assistance from neighbour, a retro flywheel remover using a steel bracket, drilled holes in it and some strong bolts. The bolts buckled a bit but with upward tension then a light tap beneath and it popped up.
2) removing the timer and base assembly. So it was jammed and due to a little corrosion wasnít turning at all, so tight when turning the throttle it clearly broke previous throttle cable. So to take off it was a long process of WD40, gentle tapping one way then the other and an hour later the movement was enough to move it left and right by hand, always applying more WD40. Then when movement was sufficient I wiggles with upward pressure and up it came.
Johnson dealer suggests that I clean with wet dry sandpaper, ultra fine sandpaper just to get the bushing and crankcase perfectly smooth then put back together. Will have a perfectly working and fixed engine then!