Whilst a Mk2 hood can be fitted to a Mk1 frame, it is better to install both Mk2 hood and frame as the Mk2 frame has the spring mechanisms to move the rear hoop as the hood folds down. If you install the Mk2 hood on to the Mk1 frame you will need to attached straps to the rear hoop and when you fold down the hood you will need to move the rear hoop yourself as you will not have the spring mechanisms.