So I took apart my Metralla 5 speed motor a few months ago. Just ordered parts and am ready to put back together. I pressed the clutch side crank bearings on the shaft and into the case. For the crank seal there is an aluminum piece that the seal fits into and a steel race that goes over the crankshaft and that the seal rides against. Should this race fit into the aluminum seal holder flush or does is there a space?

Unable to advise about the seal holder or "race", but the normal method of fitting crank bearings to either shaft or crankcases is with heat, not pressing..........

Before you fit the steel race (top hat bush) make sure you have replaced the "thin" o ring that sits next to the main bearing. I do not think the race is supposed to be flush with the seal holder, all will become clear when you put the clutch back together as the race is a spacer that will allow the primary drive chain to line up.