Yes, scraping is not really a beginner-level task, although it has been done. But removing the shims is quite simple.
You first have to measure how much up and down movement of the spindle there is. Done by grasping about a one-foot long bar in teh chuck and shaking it up and down. A dial indicator bearing on the spindle just behind the chuck will read how much movement there is. Myford specifies 3 to 4 tenths of a thou movement here. So aim at a bit under half a thou with a normal one-thou resolution test gauge.
If there is more, you adjust it by taking off the bearing caps one at a time. Do the chuck end first. It wears more. Under the bearing cap, where the hold-down bolts go through, there is a shim on each side. Sometimes the factory shims are made from a stack of two-thou shims stuck together, so you peel off the appropriate number of layers. Remove the same from both sides. If no layers are present, you can cut new shims from brass shim stock, in a U shape and put them in place. Use stock the correct thickness to reduce the spindle play. Or buy the fancy shim packs from Myford for a suitable fee and peel off the layers. When finished, measure spindle movement again and repeat process if needed.
Repeat the process for the far end bearing and spindle. Dial indicator on the spindle sticking out of the bearing and move spindle up and down with a bar up the centre of the spindle for a bit of leverage.
If the bearings are not disastrously worn, this is usually enough to bring them back to spec. If after doing the above process, there is measurable side-to-side movement of the spindle, the bearings need rescraping, which is a whole 'nuther ballgame.
PS, before taking off a bearing cap, mark it and the adjoining headstock with a centre punch mark so it always goes back on the same way round. Very important!
Edited By Hopper on 01/07/2018 12:26:54