If the bulb plug is scabby then best replaced.
Power wise 100W only 8-9amp load and 7-8amp engine running(13.2V+) so standard cable no issue really it just normally the front plugs scabby & not changed so then play up.
Do a voltage drop test & also measure feed voltage with engine running. wiring on these older jap cars has good 60% extra capability & still retain good safety margin.
Normally only issue is the standard H3 plugs corroded, sometimes earth maybe poor but that easy cleaned or renewed.
Solder, heat sleeve & tape wrap these ceramic with rubber outer weather boot ones on & should be good to go without issue >
http://www.ebay.co.uk/itm/2x-Ceramic-H4-Bulb-Holder-Headlight-Wire-Wiring-Repair-Plug-Block-Pair-/360723295200?pt=LH_DefaultDomain_3&hash=item53fcc8abe0
* If wanting do rewire do it properly & that mean separate left & right circuit & top quality relays & soldered fitting.
Last edited by Mr B on 21st April 2015, 10:27 am; edited 2 times in total