THEME:   substituting S for C in common phrases changes things   
GOOD ONES:     Get one's kicks in a painful way?   TAKE IT ON THE SHIN [not CHIN]   
Principal plant?   THE BIG SHILL [not CHILL --- this was tough]   
Pay stub?   OLA [from "payola" --- 
stub suggests the suffix, or end bit]   
Highest power?   VETO [never thought of it that way; I was awash in the metaphysical]   
Digital temperature gauge?   TOE [my favorite of the year --- toe gauges or tests temperature of bath, and a toe is a digit]   
Marathon unit: Abbr.   BBL [another toughie until one realizes Marathon is an oil company]   
Trains may stop at them   ALTARS [yet another hard one: trains are bridal wear]      
BTW:   Ally of Sun   CHAING [I wish I were on a first name basis with these historical figures of the East]      
Some like 'em tough --- guess I'm one of 'em.         
RATING:    
 
 
Three grins = Loved it; Two grins = Enjoyed it; One grin = A bit bland for my taste; One teardrop = Not much fun