Need advice. Your answers decide my trucks engine lol

I know due to the background "LS1"truck lol of the site but ill ask anyways. So I have a 1985 silverado I received from my father been in family since day one. So the truck currently has a built 406, forged crank, pistons, titanium rods, comp cam, elebrock high rise, hooker long, tubes, Mallory ign, carter 1000cfm carb, th400 trans, 12 bolt 4.10 gears, etc dynoed right over 500hp to wheels. But I have a buddy with a iron Camaro LS1 swaped and he's wanting to trade engines and idk what to choose I like the thought of LS swap but I have no idea when it comes to LS engines I'm an LT GUY LOL. Anyways his ls1 is the 5.3 iron block bored to 350 fresh rebuilt ls6 intake ported throttle body ls6 heads and all new accessorys so what should I do guys any input welcome

Personally I'm impressed with what you have! Sounds to me you have more invested in that 408 than what your getting for the 5.3? How many miles does the 408 have on it? What is your real goal with the truck? Better mpg? More power down the line? At 500hp under your hood your probably already having a blast, unless your bored I myself would drive that motor into the ground first! Just my .2 cents!

if it isn't broken.... unless the 406 is on its way out, I would keep it until it keels over.

I agree with the other guys,why swap it out?Unless you want to make it a daily driver and pick up a bit of fuel mileage,I can't see any reason to change either.

I would never ever go back to a carb motor. But in your case and the money thats already in the 406 you have then I would keep it.
fyi the iron ls1 would cost 2,500 max new just some info for ya.

also, there are a hundred other little things that will add up to make the swap happen. all of the wiring issues, fuel pump / lines, computers, motor mounts....

Why don't you put fuel injection on your 406?