You might try finding a conversion chart that tell you the differences. 35 and 40 at sea level would be on the low side, maybe time for rings and valve job. The 2ed entry on the jeep forum gives a conversion chart.
From a jeep forum;
http://www.jeepforum.com/forum/f8/at...esting-722504/
General Google search;
https://www.google.com/search?newwin...w=1280&bih=844