There is something that a lot of folks miss and that is the use of relays when doing a rewire this explains it well:
Custom Cars Classic Hotrods Streetrods-Watsons StreetWorks Here in the archives of hotrodders.com are many articles by the late Doc. Vette who helped me out a while back.Two places you never want to run without a relay is an electric fuel pump and an electric fan(these draw a large amp load),a common complaint with older cars is dim headlights even though they have been halogen upgraded.I added the relays as per the link and WOW! major lighting improvement!