318 hydraulic lifter preload.

Good piston choice in one way, IMHO. SCR should be about 9.2-9.3 with those head gaksets, typical 318 head volume of 68 cc unmilled, and those pistons. If the head volumes are more like 64 cc unmilled, like some of the earlier open chamber 318 heads, then your SCR will be up around 9.7, and you might want to nudge that back down to 9.4-9.5 with the .039" thick Felpro 1008's..... if you can return the .028" ones.

Now, be aware that the KB's are considerably lighter than the stock cast pistons, by around 100 grams for piston + pin. I don't have my notes handy to give the exact number. So a look at engine balance is in order; the bobwieght is going to change by >5%. I don't mean to be more discouraging so sorry for this tidbit of info; it's just better to know everything going in, IMHO.