two q's after some investigation:

1. Where do you source the Motolite lights from, can't find them on the web, and

2. are there two diff part numbers for a reason (maybe one if left and one is right)

Thanks

Shane

Hi Shane,
The part numbers denote that one is an H4(high low beam) light with parker lamp and the other is an H1(high beam only).The H4 takes the normal type high/low globe and the H1 takes the normal single globe that the alfa has.I reuse the standard wiring for the H4 with the lugs changed to 4mm female spade lugs pushed onto the lamp with ordinary spade lugs to connect the parker lamp or you can solder the parker wires to the lugs in the gtv6 plugs,depending on what equipment and skills you have. On the H1 I use the standard high beam wiring.I buy the lights from Car torque Products but your local Sprints/Auto Pro/Supercheap etc should be able to source them for you.You can also fit Hella lamps etc of the correct diameter but they wont press in or  allow you to refit the chrome trim if you have it,you will have to do a little more fitting work and glue them in with silicone or uerethane.
Cheers
Andrew

Hi Shane,
No worries,I thought I should include some more tips on the how.
When I said 4mm lugs I should have said 4mm wire 8mm blade spade lugs,the normal spade is 6mm wide and the bigger one is 8mm wide.You can use either but on the H4 globes the lugs are 8mm and on the H1 they are also 8mm.I use 8mm lugs on the H4 so that if you have to change a globe it is just unplug and replug,I use 6mm lugs on the H1 so that I can reuse original wiring when it is in good order by just cutting down the 8mm lugs on the new light with good tin snips,you should be able to see it in the pics.You can also see the tabs on the new light which I cut in the middle and then bend into a U shape and twist off with a good pair of stout-sharp pointy nose pliers(by sharp I mean new) for good grip.Just be sure when you get the RG2502 (H4Lamps) that they have the parker lamps in them,sometimes I get them without which is fine for older alfetta GTV'S but not GTV6 or later GTV,S.I will attatch a picture of a couple of Hellas as well.

Andrew,

Do you notice much difference between the quality (w.r.t. illumination) of the Motolite & Hella?

The Motolites would seem to be the better solution: good fit, re-use the chrome ring. S so is there any advantage going to Hella?

Good stuff, thanks

AL.

Yeah, I never thought i would find headlights so interesting....

i'll pay, you build.  distance is no issue