You can save yourself a lot of work by using a rear view mirror mounting kit preferably the type with the metal button - comes complete with all the surface prep agent and isocy - adhesive to stick the metal button to glass - in this case the back of your secondary. The stalk is 3/4" dia and conviently includes a STIFF ball joint to get approx alignment leaving you to fine trim elsewhere. The button is held in with a hex grub screw allowing the secondary to be easily removed without spoiling the alignment. I've mounted a 2.5" secondary this way - no problems. Uses the stalk from a 19 yr old Pinto :-)
TrakAuto stock the adhesives for metal buttons but may only have complete kits with plastic buttons which use RTV adhesive. I avoided these since they didn't include surface prep agents and I wasn't sure if the mirror back was 'clean' . Also I couldn't be sure the plastic would not 'creep' losing the alignment.
This proprietary deisgn is freely made available for non-profit use only. copyright 1994,1995 for commercial use or further information contact: john.houldsworth@controls.eurotherm.com
Regards, John H
______________________________________________________________________ John Houldsworth Direct phone (703) 787 3414 Vice President R & D FAX line (703) 787 3447 Eurotherm Controls Inc 11485 Sunset Hills Rd, Reston, VA 22090 john.houldsworth@controls.eurotherm.com ______________________________________________________________________