Ok, I had a bit too much fun last night...but I'll try to give it a shot. I apologize if this is a rather long post, but there is a lot to cover, and I'm going to try to give you as much detail as my poor old self-abused brain can remember..lol
First you will want to take off your old intake, flip it over, remove the egr and tap/plug that hole. You can use a brass plug with a hex or allen head. Then spray the dickens out of the air injection rail nozzles with some type of penetrating lubricant like WD-40 and let them set for a while. Then go back and
carefully loosen them to remove the air injection rail. Cut the air injection rail tubing off at the nozzles, take it out of the nozzles, and thread the center of the nozzles so you can plug them securily with some black grade 8 allen screws and small thin brass washers (you can get those at any hardware store real cheap) and re-install them back in the head so that there is no leak there.
Then the big crossover pipe that runs from the exhaust to the intake around the backside of your engine will have to be soaked for a while with WD-40 where it connects to your exhaust too, both ends loosened
carefully and removed. There is no plug known to man (that I could find anyway...lol) to plug these openings in your intake/exhaust off, so I recommend just cutting the tube, removing it from the fittings, welding the fittings shut, and re-installing them. All that is left then is to remove your smog pump, and all of the rest of the emissions stuff,and plug off any unnecessary vacuum lines. BTW...if you decide you want to remove any leftover ugly studs that are sticking out from where your smog pump, brackets, etc, were bolted on to your engine, be sure you put bolts with copper or aluminum washers back in to seal/plug them all or you will create an embarassing oil leak. (Been there...done that...lol)
However - I highly recommend that if you ever want to pass smog or sell your truck in the future to anyone that may have to - that you remove your old carb/intake, your exhaust manifold, crossover tube, air injection rail, smog pump, and all of your emission stuff and set it aside. And you should track down another air injection rail for the nozzles and another crossover pipe to use to plug their holes off. That way you can revert it all back to stock if you ever need/have to.
Or not - it's your truck. Just know that if you don't - puting it all back on and getting it all back to stock will be a huge major PITA. So you decide.
Then I would also recommend that you get an Offy intake from Mokadeth. BTW...he's the sole world-wide distributor for them because he argued and pleaded for months and finally convinced Offy to make 25 of them (for which he had to pay for all 25 of them in advance plus shipping out of his own pocket) after they had decided to discontinue making them. He still has a few left, but the supply is limited, and when they are all gone - that's it. He did that just for us guys at luvtruck.com and rumor has it that he's a real nice guy...lol
A header would also make a big improvement. Pacesetter makes a decent one and you get those on Ebay for a reasonable price if you do a thorough search and compare prices. They come with a flange and a connector that can easily be hooked up to your existing tail pipe.
I also recommend that you pick up a used Weber 32/36 carb from Ebay, grab a complete rebuild kit there too, and put them both on. (That's the cheapest way to get a Weber carb and will save you a bunch of $$.) I recommend the electric choke model because it's a simple one wire hookup to any 12 volt source under your hood that's got power when the key is on, and they are very reliable.
There is a free downloadable file on everthing about all carbs made by Weber here on the site that Ben has put in the Information page on the front page of this site for all of us to use. Here's the link:
http://www.luvtruck.com/pdf/Weber_files.exe . You can download that file to where ever you want and just click on it and it will unpack itself it a folder full of .pdf files that you can read in Adobe Reader. (If you don't have it already you can download for free here :
http://www.adobe.com/products/acrobat/readstep2.html) While you at it you might want to snoop around in the Information and the Links section on the front page because there is a ton of other good stuff there.
The Offy intake, Pacesetter header, and Weber combo is the best thing for performance on a de-smogged 1.8 G180 Luv engine you will ever find, and IMHO the Luv's stock emissions crap with Isuzu's stock intake/carb/exhaust combo is one of the biggest POS pile of junk parts ever made. (And your truck will Luv you forever for removing/replacing them all...lol)
The only thing else I would add to this project is a reground cam from Delta Cams. Here's there link if you want it:
http://www.deltacam.com/ , but there site is currently be re-done, so here's their toll-free number : 1-800-562-5500. If you send them your old cam, they will re-do it to whatever specs you want (from mild to wild...lol) for a reasonable price and return it back to you quickly. They have been doing cams for over 30 years and IMHO are the best in the business at it. Just remember to lube it up real good with some cam assembly lube and re-set your valves when you re-install it before you fire up your engine.
That's about all I can think to add on an obviously very boring Sunday. There quite a few other guys here that have done all of this to their trucks already that I'm sure will point out something I goofed on or missed....lol So if you need anything else or have any other question...just holla.
Good luck and have fun working on your truck!