What do I need for lubing my ICS upper gearbox?

[Queboo12]

Hey, just wondering if you could help me with this simple problem.
So basically have a ICS upper Gearbox in pieces. As soon as my downgraded spring arrives, going to be lobbing that in it to replace the spring already in it. So during the re installment when I receive the spring, I am going to re-lube the whole upper gearbox (split gearbox design) and was wondering what lube or whatever do in need in doing this. I keep looking at videos on youtube say use this lube, use that, then this gun grease and I am completely confused. :/ I already have this silicon 3 in 1 thing spray which has been verified by a post a while back being 100% suitable for airsoft. So what else do I need?
Cheers guys/gals!
Regards

[Boo-Sabum Ben]

Lithium grease on the gears, silicone grease in the cylinder