OK ive had the filler neck re located on my tank but there are no outlets for a breather all have been plated and welded by previous owner my question is what do I do, do I need to have a pipe welded on or can I buy a special filler cap any help please its my first build so don't have a clue on this one thanks hopefully ill be ready for next summer

https://www.merlinmotorsport.co.uk/s/fuel-system/fuel-caps/aston

Filler caps such as these above are breathable.  So you wont need a vent pipe. 
What sort of filler cap are you going for?

just wanted a standard one chrome as its in the middle of bonnet but not too expensive otherwise ill have a breather fitted cheers

Whatever cap you choose if it's not vented you could always drill a small (1mm) hole in it. There's no need for anything fancier.

thanks nice advice and cheap ill have a look at my cap