Fork oil for SBK forks on 900SS

I have 996 forks on my 900SS CR. I'm going to put in new fork springs, 0.9 to replace the 1.0's in there (200 lb rider weight). What weight fork oil should I use and what level should the oil be measured at? Racetech recommends their 2.5/5w but I don't feel like paying $50 for fork oil. The fork internals are stock -- can't afford the Gold valve kit just yet.

.9 kg springs should be for about a 160 lb rider. Are you sure you are not going too soft? I weigh 150 lbs (no clothes) and I use .85-.90 kg springs on my 1997 900 SP (stock forks and SBK conversion). I don't know what level, but any 5wt. fork oil is about right.
Joe

Racetech's site calls for 0.9 for the street. I had 0.85 in the Marzocchi's (about 10 lbs ago) and they worked fine. The 1.0's in there are too stiff.