Shell Vitrea 33 is specified for the lubrication of all parts (apart from the gearbox).
Shell Vitrea 37 is specified for use in the gearbox.
Both Shell Vitrea 33 and 37 are pretty close to each other in terms of viscosity. It is generally accepted that Vitrea 33 was replaced with Shell Vitrea ISO VG 68 when ISO standardisation came in, and 37 was discontinued altogether. Vitrea 41 became Vitrea ISO VG 100, so you can see that Vitrea 37 lies somewhere between ISO 68 and ISO 100. You are unlikely to notice much difference between ISO VG 68 and ISO VG 100, but if you feel that you want a thicker oil for the gearbox, then you should choose ISO VG 100.
The whole Vitrea line of oils were discontinued some decades ago. Some grades were replaced with equivalent oils in the Shell Morlina range, but the ISO 68 and 100 viscosities are no longer available either. The old Vitrea line of oils (and the Morlina oils that replaced them) do not contain any of the more advanced EP additives that you sometimes find in gearbox and similar oils, which can sometimes attack brass/bronze components in old machinery.
For applications that specify the use of the old Vitrea oils, we recommend the Mobil DTE Named range, which are a good quality machine oil, well suited for this application. It is safe to use on bronze/brass components found in old machinery. We recommend the use of Mobil DTE Oil Heavy/Medium to replace both Vitrea oils, unless you need a slightly thicker oil for the gearbox, in which case use DTE Heavy/Medium in all areas except for DTE Heavy in the gearbox.
For use on the machine slideways, we recommend either Mobil Vactra Oil No.2/Shell Tonna S3 M 68 on the horizontal slideways and Mobil Vactra Oil No.4/Shell Tonna S3 M 220 on the vertical slideways.
Shell Alvania Grease 2 is specified for use on the Vertical Attachment and Rotary Tables. This has been replaced with Shell Gadus S2 V 100 2.
Shell Alvania Grease 3 is specified for use on the Spindle Bearings. This has been replaced with Shell Gadus S2 V 100 3.