T.A. Criterium nail-on shoe cleats

Not that difficult to get, but I've just received a new pair of nail-on shoe cleats. I absolutely need these, because I want to ride with my Vittoria shoes and Campagnolo Pista pedals. Although my shoes have threads for newer type cleats, I will nail these T.A. cleats under my soles. These are age-appropriate and I've used similar ones for years and years. Not exactly these T.A. Criterium Réf: 36, but mostly the T.A. "J. Anquetil" Piste Réf: 59. I also used the Calrouge, but I couldn't find a pair for a reasonable price. I think the Criterium has a bit more play/freedom than the more fixed Piste. Because I'm used to floating cleats now, I think I prefer these. A nice gallery of pedals, toeclips, straps and cleats can be found on Speedplay's website.
Before hammering the cleats on my shoes, I first have to find the proper position. This is how I used to do it (and with me many others. Ride the bike with the cycling shoes, but without any cleats. Try to ride with a nice and smooth pedalling stroke and make sure that the position of the feet feels good and natural. After some ridding, there will be markings of the pedal cages on the new soles. This is where the cleats have to be positioned. Of course, it's recommended to compare this position with your other shoes and see if there is a match. Once the shoes have been used for a while, the markings become more and more visible. When the cleats are worn (due to walking and riding), it's easy to find the correct place for the replacement cleats.