Just installed my homelink mirror -- the DIY was really helpful.
1) I had previously replaced my overhead console and got it out the 'hard way' using strategically placed screwdrivers. Removing the visor catch screws was much easier. I wish I had known this the first time!
2) The 'straw trick' worked great.
3) Getting the fabric tape off the end of the rubber grommet was kind of pain. Mainly done just by picking at it.
4) Getting the mirror end connector open was kind of tricky -- even with the great picture. I wound up using a jewelers screwdriver inserted in the middle of the 'bottom' of the connector to simultaneous release the latches on either side.
5) I feel kind of stupid for saying this -- but I didn't know the pins weren't symmetric -- but that one side has a 'clip' to lock it in place once inserted. This clip must go on the outside of the connector. I realized this only when I had trouble getting the first pin to go in.
6) Calibrating the compass is done by sticking something sharp into the 'hole' (not really a button) on the bottom of the mirror.
Overall took about 1:15 (including calibration and programming). Without this DIY, it would have taken me much longer.