Identification Help needed

Hi everyone.I was hoping someone may be able to help me identify a frame I am intending to rebuild.It seems to date from the mid 60's.It had a Williams crank date of 1965, Nervex lugs,Campag dropouts and chromed forks,rear stays and seat tube lugs.and wrap over seat stays.All the decals had gone as it had been repainted but when I've rubbed it back the original colour seems to have been powder blue with a white head tube.I 've included photos of the Nervex bottom bracket which has the Nervex code plus two other serial numbers which is where I need your help.
81768 and S6336 . It also has A 7 stamped either side of the seat post lug?.Any help would be gratefully received as I would like to try and source the original decals once its painted.

The '7' is probably the remains of '72' which is the lug angle.

Thanks Old Ned you are right-on further rubbing away of the paint I have revealed a number "2" so it is 72.

Sort of reminds me of a Carlton Flyer seat cluster..........they came with the option of Nervex lugs if memory serves.

Shaun

Thanks but the lugs are not the same on the Carlton Flyers

nervex pro lugs made 50's & 60's I believe so I guess still making them in the 70's with the 72 stamp??