When your ready you can send off a bag of bits to get plated, they do "clear" (sliver to us) or yellow (gold to us) for about £30.
Its not worth spray painting tbh as it wont last (bits like door catches)
I got my Clio wheel bolts done while my wheels where away being powder coated, that was almost 2 years ago now and they still look like new.
Great project btw, your doing a cracking job.
Sounds decent, once it's up and running I'll then start "tarting it up" I did originally want to rebuild it to a minty fresh condition, but I've quickly realised that it'll be a long wait if I do it that way! So for now, it'll just have to be 'very nice' then in time, I'll get it fully mint.