Ah well-call me green... Sorry guys, I did not know that the crankset mattered-I figured that a bike needed a certain chainline and that this was provided by a certain axle length that would be standard for that model bike! Hmmm-in that case, this may be trickier than I thought...
The bike is a Peugeot PSN10e from the 70s. I lost the Stronglight BB which was to be replaced anyway. I held a Shimano UN73 BB axle length 107 where it would all go, and with the 105 crankset on the square splines this seems fine, but I cannot be sure. The objective is to fit a Shimano 105 Octalink Crankset and D/A Octalink BB. Does this help? Please let me know if I am missing something...