When it comes from going from this point to the battery via the 35a fuse is 16 amp wire ok?
Yes. The fuse must be the 35A blow
(17.5A continuous) type and the 35A blow fuse is used with original 14/32 8A wiring.
The modern equivalent fuses (blade fuses etc.) are 15A or 20A as they are continuous rated
I could use two together. When the fuse was on the negative side the original single wire was ok.
The side of the battery the fuse is on makes no difference to the amp rating.