I originally built my "Aberg Replica" in 1980/81 using the frame of my 1978 390 AMX.
This picture id from 1981 just after I built it and before it first race.
The front end is YZ465G that I bought new for the project as the std 35mm front forks flexed quite a bit, the fox shox were what I had been using while I raced it prior to the conversion from Auto to the SR500 engine.
So I didn't have to make any permenant modifications to the frame I made an oil tank from steel sheet, with the intention of making an alloy one if it worked ok, however, I never got around to making the alloy tank.
It was resurected for CD2 with a TT500 engine and YZ125 tank fitted;
A couple of years ago, I removed the 500 Yamaha engine and refitted the original Husky engine and forks etc. I do have a 1978 CR250 Husky frame that I intend to rebuild it on once I clear some of the other projects that I am working on. When I do eventually rebuild it in the 1978 CR frame, I will build it up on shorter (10") suspension, mainly because I and getting to old and decrepid to climb up onto real tall bikes, and because I don't like the look of the ultra tall modern replica that seem to abound now days.
CJ