I just did this (for the first time) on my '93 xrl last weekend. According to Clymer, you turn the crank to TDC on the compression stroke. All four valves will have play in them on the compression stroke and all four can be adjusted. If you are at TDC and two of the valves are open (no play), you are on the top of the exhaust stroke and the crank should be turned another 360 degree. I am not convinced that my fat, flat auto feeler gauges were the right tool for the job. It seemed there was a lot of bending and twisting to get the gauge into the gap. I think next time I'll get gauges specifically for the task. Good luck. I'm probably using the same ones you have, just carefully bend the last 1/2" or so at a bit of an angle as needed and they will work fine. To be correct, the feeler shouldn't be rubbing on the head cover (the area where the cap screws in).