Opinions differ on ls heads. I've seen some say the heads are sloppy from gm, they all need decked and a valve job straight out of the box. others say it doesn't matter at all, sloppy mechanic the build, and it will hold 700hp all day long reusing everything from 200k miles junk yard 5.3. even all the torque to yield bolts they say you can't. I've seen lab tests showing a reused tty head bolt is actually stronger than a new one, since it's already pulled to its limits. the tricky part is what tq spec do your use to take it back to that point. but again, that's a high hp build that will stress it's head gaskets with a power adder not your daily that idles down the road at 1/8 throttle.
both ways seem to be correct. if you're doing it yourself, it would he your call. since it's a shop, you're kinda stuck with how they want to do it, since most shops won't even rebuild an engine anymore, especially a hybrid one. they just buy reman and drop in. I was recently in a training class and got to talking to the instructor. he said his last job was working for an insurance company and all he did was drive around the region and disable hybrid car batteries for shops that were scared to touch them. like he literally got paid to drive around, stop at a shop, pull the orange plug on the battery. use a volt meter to prove to the tech it wasn't going to murder him and then drive away. Come back when it was done and push the plug back in. no opening batterys or anything, just the one orange plug. the lack of intelligence in automotive repair these days is depressing.
personally, when mine starts ticking from lifters, I'm going to pull the heads, replace the lifters with some gm ones, would almost rather good used ones than new gm ones, since all new parts have a high failure rate these days. if the cam lobes look good, new head gaskets, reuse everything they say you shouldn't and slame it back together and roll on. end of the day it's a very good 6.0 ls engine that putts around under 3000 rpm 99.9% of the time. putting out what, maybe 150hp at 1/4 throttle it's whole life? if it wasn't for shootty lifter design. they would last a million miles with just oil changes.
no need to build a blue print race engine out of it.
just my 2 cents
