Found this:
while doing research on it, But doesnt address the bumper... the issue in question

 

I went from a 1998 front clip to the GMC clip and used the original bumper reinforce

ment behind the front cover. Stock second generation radiator support, GMC (Envoy HID in this case) lights, bumper cover, and grill. The bumper cover should match the grille used. So, if you're using the Blazer stuff use a S10 /Blazer cover with S10/Blazer grille setup and the matching lights. Does this help?

 

Yes it helps,
I know the covers need to match the lights, Blazer bumper with Blazer grille/Blazer lights
Just wonder if both Bumpers bolt on the same, I know lights and grille are same for both Jimmy and Blazer

I didnt know Envoy did HID, I will look into it

 

What did you have to Modify on the Envoy lights to fit the Jimmy?

 

From 1998-2000, there was a Jimmy trim called the Envoy....had a fancy interior, neon spoiler rear light, and some had these neato mosquito headlights on them.
In 2002, GMC made the Envoy based off the larger Trailblazer frame. Kind of confusing, since the S10 Blazer had a trim called the Trailblazer for a few years, as well.

 

And learning is half the power!

 

The lights interchange with any Jimmy type front. The trick is finding them with good ballasts. Be forewarned that everything about them is expensive too. Just good lenses alone run about 250.00 if they're nice and clear. The ballasts are also pretty large and mount down on the bumper reinforcement also, not easy to get at. I also suggest that when a person runs them, if their vehicle didn't come with them that you have a harness that is relay controlled and that they pull their current straight from the battery. If you use a stock harness sometimes the initial firing can pull enough juice to fry wiring. It's kind of hit and miss but I don't suggest that a person just plug in the factory harness and call it good.

 

Also, the HID lights came as an option on some Diamond Edition Jimmys.

 

OK
I think I am going to go with the blazer front end.
the mounts are not expensive and the main reason for this was headlights and being able to see better at night...
I am using the best Halogens i can find.. i tried LED but they disperse too much in Jimmy Housing.
Just want a good Headlight.
I will search for blazer front ends and order HID blazer lights

 

Might look into blazen_red's HID retrofit thread. That's the direction I'm headed.