As for the wiring, i'd suggest to do up the wiring new, with 2 relays one for each side, with high gauge wires and casings
Use good relays, either OEM Japanese headlight relays or Good brand new ones like Hella etc, also use a relay for parking lights
As for the seal beams, get rid of them
the first gen pajero came with a round light that was flat, not curved like the seal beams, it had a mitsubishi badge in the middle and letters halogen across etched in the glass, made by koito or stanley
https://www.ebay.co.uk/itm/ROUND-HEAD-LAMP-LIGHT-for-MITSUBISHI-PAJERO-SHOGUN-MK2-1991-1993-/380599713598
the above is very common in shops here
then you have the capability to get the period correct upgrade, the bulb is H4
thereafter H4 you have the following options
Stick to a warm colour, so that it looks correct with the cars vintage
Standard koito bulbs or Pair of night breakers, or warm HIDs <4000K or LEDs <4000K all mounted to the H4 socket
Also sand down all grounding points and re-anchor them or you make have flickering issues or dim lights, lubricate the light stalk and connectors if they are rusty.