Hi. My 1998 Polaris Sportsman 500 has one stripped valve cover bolt hole, and another valve cover bolt broken in half in the hole. I used it two seasons before it started to leak oil. My question is : would it be simpler to just bore the stripped hole one size bigger, tap new threads and use the corresponding lerger bolt, and do the same in the other hole after drilling and removing the broken half of the bolt remaining in the hole Or use heli coils and stay with same size bolts? Suggestions appreciated. Thanks and greetings from chilly Québec where wood stove has now been going for 8 months….sigh.