1995 Buick Riviera Owner's Manual - Page 243
1995 Buick Riviera Manual
Page 243 highlights
It is r e c o m e n d d that theupper Limit not exceed plus 0.4 degrees .from the center the bubble. Other drivers o€ may flash their brig& lights at you if your adjustment i s much above plus0.4 degrees. The headlamp aiming device is under tbe hood, directly behind the headamps.