I wanted to do the valve adjustment maintenance so I proceeded to take off the valve inspection covers to no avail. It took a few days but with some heat and penetrating oil i was able to take off the exhaust caps. Unfortunately I was not so lucky with the intake caps. After heaving, heating and oiling I finally... Stripped it. Are these things torqued to like 100 ft-lbs or something. The caps on the exhaust side are in pristine condition. I don't know why they are so hard to take off. Any suggestions???