I used the enclosed insert as show in above reply, in my 912 front suspension and I tried the old used 912 insert in my 911 strut and it will not fit.
The part I am thinking is the Part which Pelican offerer's Part # 86-1647. Called Koni insert for Boge strut.
The insert has the check valve on the bottom and the strut housing it self is the reservoir.
By the way, it's a 911T 1972
