No problems as such, it is just that the catch is set up differently between the mono subframe and the twin subframe, so you need to take the current arrangement apart, put some of the pieces to one side and then re-fit it. I haven't got any pics to show you, but you'll see when you try it for yourself :thumbup
The other thing is the seat pad. You need a pre 2000.5 seat pad as none of the others will fit. A later model subframe will fit, but not the seat pad with your current tail piece bodywork. The seat pad you are looking for has a pointed tail to it. The later ones are squared off.