obscure brake line question

[speedo]

Replacing the front suspension on a 914 (stock struts), with a 74 911 front 5 bolt suspension. The flexible rubber short line (stock 914) from the chassis to the flange on the 911 struts (where it mates with the hard line to the caliper), doesn't fit the 14mm opening on the 911 strut flange. That end of the brake line is 16mm. Thinking that that rubber line might be specific to 914 struts...I went and checked my "extra" brake line box and pulled a couple used front rubber lines out to measure and they are also 16mm. In fact all the used lines I have are 16mm on that end. Am I missing something? The flange on the 911 struts doesn't look modified...but maybe it was to run different manufactures brakes? Is that opening on the flange supposed to be 16mm for 911 and 914? I can just ream that flange to accept the 16mm line end, but I would like to understand why the difference?

Thanks in advance!