Keep it simple, for USD forks what you need is the entire GSXR 750 SRAD (1996-1999) front end for a Curvy and for RWU forks the entire GSXR 600 SRAD (1996-2000) front end (bear in mind many GSXR parts are interchangeable between models)....
Yokes,
Forks,
Wheel,
Spindle,
Brake Discs,
Brake Calipers, and the
Fender.
In addition you will need
TL1000S clip-ons for the 750 forks as the GSXR ones are two low and the throttle cables will damage the fairings. To make it all work the simplest method is to buy a bearing from Twin Works Factory, this replaces the top bearing on the SV and allows for the bigger SRAD stem to pass through. The lower SV bearing can be retained as it is a shared part with the GSXR's.
I have fitted 27 front ends to Curvy's in the past 9 years, and 4 have had steering lock alignment issues (which is a bit strange for a mass produced bike and parts). The simplest way to over come this, and the best if you want to return to the SV front end in the future, is to file off 1mm from the SRAD's right hand side steering lock tab. This will allow the SV's handle bars to lock and cause no permanent damage to the bikes frame or ignition barrel.
Another method to mount the yokes, without the TWF bearing is a little more time consuming. You need an SV steering stem for the SRAD bottom yoke, however it is a smaller diameter than the SRAD's so you will have to braze some metal on and then mill it down to the correct size. A shim (spacer) is also required for the top yoke as the SV steering stem is a smaller diameter up there too. The advantages of this method is that the bike retains all its original headrace bearings, thus making them easier and quicker to get hold of.
The one problem you will be left with, whether you go USD or RWU is the speedo. The SV650 runs it speedo off of the front wheel and the SRAD wheel has no location for it and the SRAD spindle has no space and is to large a diameter to except the speedo unit. There are three option to take, one is to run with no speedo, another is to use a Hall Effect sensor (
Northwind and
Yorkie Chris are your experts here
), and the final option is to run the standard SV speedo off of the rear wheel.
The above USD fork option is only applicable to Curvy SV's (1999-2002).