Nortons - General

Could anyone advise me if a multi grade oil (Millers classic pistoneeze 20W50 would be ok to put in my M50 gearbox? .

I've been given a beautiful polyester tank for my Surrogate Manx racer project. However, the inside is a mess and definitely needs a proper coating.

I went to the Motorcycle Live Show at the NEC today. I mistakenly thought that Monday would be quiet rather than a weekend, but no, it was full of people.

An elderly Dominator 99 I purchased has been fitted with bronze clutch plated bearing on steel plates. The clutch slips with the engine loaded, before full throttle.

Hi I have just purchased a beautiful Dominator 99 Deluxe and become a club member. Pic attached. 
I have a couple of questions if I may.... 

Just read my very late copy of RH magazine and my hopes and heart have been boosted.  In the letters section there is a request to celebrate the " 75th Anniversary of the Featherded-framed Manx Nortons"  next year.

I am replacing the swing arm gusset plate on my slimline frame and wanted to know if there is anybody out there that can re-stamp the identification numbers to the new gusset plate?

Hello.Can somebody tell me if it's possible to tell what sort of bike a feather bed frame is from using the frame numbers. 

Thanks. 
Nick.

Today I bought a pair of roadholder forks on an autojumble, including yokes. The yokes have a width of 7" and the fork measures (from top of nut, to bottom of the lower slider) 31,5".

I have recently acquired a Norton Model 50 1959 wideline.  On taking the petrol tank of to get access to the carburettor I noticed a crease in the right side top tubing similar to the one on the attached photo.