MTC Piston Button Installation

OK,...So I just received a rebore kit from Pit Stop Performance for my 78 KZ1000 and I have a question that is hopefully answered easily by someone here in the KZR forum. They come with buttons not circlips.

The piston buttons have a flatter side and a rounder side. Which side points in and which side points towards the piston liner? Also, do you just push them in?, if so will they rub against the liner?
Thanks for the help.
Jim

Flat side goes in towards wrist pin ends,match curve on other end with bore.

As above ,and yes they just push in.
They will run against the liner but there is a clearance when pushed fully home against the wrist pin so there won't be any real force between them and the liner to cause excessive wear.
They are also Teflon to reduce friction when that occurs.

Thanks for the info on the previous question.
One more question,...I know I am supposed to coat the piston cylinders and the pistons/rings prior to installation but I am getting conflicting information. I have read that I should use regular oil but my manual says use high temp grease.
Which should I use?

Lightly oil the piston skirts with the oil you are going to use or some proper engine assembly compound such as Graphogen.
Don't go mad with the lube as it will inhibit the running in process and can actually prevent the rings and bore bedding in correctly which will result in a lower compression.

Like stated the buttons will rub the cylinders without issue. I prefer to use transmission fluid in the cylinders or some WD-40. Ring seat is faster and works fine.