Well, seeing as you ask. Firstly let's remove the headstock and get some rake on it, enough for 12" over stantions should do. Secondly we need a bit of rigidity on that back end, so lets have the back of the frame sliced off, along with all that sissy suspension, and a few tubes welded back on. Lastly spend years fabricating parts to fit, spending thousands £££££'s on the way. Finish off with trick paint in a garish colour and bingo!
Failing that, you could try and do a sympathetic restoration on the tank pinstripes, and replace the B.S.A. sticker on the timing side which looks too low down to me. Finally some downpipes and a bit of elbow grease would give it a nice 'lift'. I'd leave it at that then.................Nice bike!