You see, fear can be overcome. (We call that courage.) But lack of confidence can cripple you.
Last October or November, I got a Leatherwood sight mount and rangefinding ballistic-compensating 'scope for my M14. When I went to install it, I discovered that it did not actually fit. I eventually figured out, through careful measurement and comparison to a GI M14 receiver spec drawing, that the reason it did not fit was because the manufacturer of my M14 omitted one flat cut from the top of the front receiver ring, leaving the front ring too tall by about .065".
Well, I happen to know a couple of extremely good machinists. So I talked to one of them about cutting a little metal from the interfering area on the mount to make it fit. But he was too busy at the time, and, well, one way and another, it never happened. Having had a rifle ruined once before by a gunsmith of previously unknown reputation, I was hesitant to take it to a local gunsmith. So instead, I basically sat and vacillated for about eight months, never managing to find the confidence to just do the job myself.
Today, bored and frustrated, I finally hit one of those shit-or-get-off-the-pot moments when I found the still untouched mount sitting on a shelf above my desk while tidying the shelves. So I took down the mount, got my M14 out of the safe, took both to my workshop, stripped the M14, set a small bowl of water on my bench for cooling the workpiece, and set to work.
It took me about thirty minutes, all told, working purely by calibrated eyeball, to decide exactly what needed to be done, grind the offending area to a closer and more stable fit than the unmodified mount would have been on a GI spec receiver, finish-grind the cut surface by hand on a diamond hone, and deburr all affected edges with a superfine Arkansas stone. It now fits so precisely you couldn't slip a sheet of tinfoil into the reworked area, let alone paper. Then it took me maybe another thirty minutes to reassemble the rifle, install the mount, mount the 'scope, and eyeball level it.
Now I need to get the rifle and a spotting 'scope out to a decent rifle range and zero it in at two hundred yards. (The sight, a first-generation Springfield Armory 4-14x56 Government Model, is calibrated for a 200-yard zero with 7.62mm M852 match ammunition, 168gr BTHP at 2550fps, though M118 ball should be pretty close too. Most of my 7.62mm ammunition is M80 ball, but that'll do for initial zeroing.)
I could have done this eight months ago. But so many things have gone wrong, for so long, that I lacked the confidence in my own skills to start the task.
Lack of confidence is the mind-killer.