Since the 3:2 pulldown is completely reversible (unlike true interlaced video) I think you’ll find converting your 60fps capture back into frame accurate (capable of being GOUT Sync’d) full frames at 23.976 fps with no interlacing and no duplicates is much harder than if you just capture it at 29.97 and then IVTC it with a single line in an AVISynth script:

AVISource(“c:\path\to\my_29_97_LD_Capture.avi”).Tfm().tdecimate()

Or simply open it in Virtualdub, go to Video -> Filters -> Add -> IVTC and choose Reduce Frame Rate, Auto, Adaptive, Click OK and then save your file.