Kitamura MyCenter4 rebuild, spindle lubrication

Hello to all,

As I am new on this forum, I'll shortly introduce myself first:
I'm Bart, 26 years old. I live in Belgium (Europe) and saved an old Kitamura MyCenter4 mill from the travel towards the scrapyard.
The machine itself had a Fanuc 6M control with all control and drives defective due a lightning stroke. I bought it from a guy who planned to rebuild this machine with a modern control but he haven't got the time to do it.
So I decided to rebuild it by myself for hobby milling.

So far, I retrofitted a 6 axis CNC controller from CsLab, the CSMIO/IP-A
Also placed the Argon DC servo drives from Granite Devices. I installed Mach3 on a PC and everything runs good, so far so good.
Now I'm just waiting for my VFD to drive the spindle . But I have a question about the spindle and gearbox lubrication. There is a small oil pump on top of the gearbox for lubricating the gears and spindle bearings. The pump runs fine but I'm wondering if I can see the lubrication to check if there are no lines blocked as the machine didn't run for several years now. I didn't have any part list or disassembly drawing from the spindle with my machine.
So my question, is there someone who can help me so I can safely test my VFD on the spindle without damaging the spindle bearings and gears?

If this last step works well, it means that another CNC machine is saved from scrapyard death! :)

KR, Bart