Attached is the compare between tooling top gauge and actual lasted upper top gauge difference.You can find from 14.5UK to 17UK, tooling top gauge is much shorter than that on lasted upper, which is the main reason to cause difficulty for assembling.Solution is resize 15 16 17 tooling to be 14.5 15 16/17. Means original 14.5UK mold will be removed. No additional mold is needed