When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
With the expense involved with Nikasil why mess around with old pistons. Also pistons designed for alusil are incompatible with Nikasil, Alusil pistons have an iron based coating. I would be buying a set of new pistons one size over to suit Nikasil, JE or Mahle. Send them with the block to millenium so the clearance can be set perfectly to each piston.