You'll find a lot of details here:
http://egli-vincent.net/2014/05/03/the-egli-laverda-another-way-to-touch-the-egli-myth/
and here:
http://www.1000ps.at/modellnews-2348791-egli-laverda-sfc-750
BTW: if someone wants to have a brand new frame, I know who makes them in Germany (including EGLI certificate). Send me a PN and I'll forward contact details. It is a bare frame-Base, not a complete polished and chromed/nickel plated frame so you can weld additional fasteners on it where you need them to be.