swapping valve-springs/ rockers WITHOUT pulling the head???

[87-325ic]

I need to install new valve springs and might as well do rocker arms while im there. I dont want to have to pull the head.
obviously i plan to do TB and WP in the process, either way

Has anyone here actually done this? Or, at least, heard of someone doing it?
How much fuckery was involved? What made it work?
Is it easier to just pull the head?

Reasons to not just pull the head:
-I dont want to pull the manifold and turbo again. need more gaskets.
-I dont want to re-use the MLS headgasket, I dont want to buy a new one. Nor do I want to go back to a stock one.
-I dont think i need to rebuild anything else on the head, the motor should have been fairly refreshed about 50k miles ago.
-It could be easier.

Reasons to just pull the head:
-Take off the exhaust mani, and be able to get it welded to route the wastegate back into exhaust ( im tired of the noise, and want to hear more turbo )
-Any needed refresh of the head stuff.. Anything else I should do while doing the springs?
-pulling the intake manifold and re-doing gaskets there and especially the bitch tube o-ring i think is leaking..
-It might just be easier to actually do the valve springs.


Reason for valve springs:
I think i am getting valve float at high rpm, worsened with higher boost.
Motor has a 272 cam, 8psi wg spring.. running 13-15psi (at 1mi elev.) with ebc.
and old stock valve springs.

[nando]

it can be done but it's not easy. You need to work the rockers like a puzzle - they need to be slid off the ends of the valves so none of them are tensioned by the cam. Once they are all off the valves, you can slide the shaft out of the way. But it won't be easy in the car, most people can't even do it on a bench and just hammer the shafts out (which is the wrong way anyway).

[digger]

I think I'd have a dummy spit trying to do all valve springs with head installed.

[jeffnhiscars]

Why would you want to change valves springs and rockers and nothing else

[87-325ic]

what else should i be thinking of while in there?
motor was suposedly rebuilt 50k ago, so dont want to do too much.

ive pulled a head apart on the bench. one rocker shaft didnt come out, even with a hammer. the other slid out like a perfectly matched, oiled shaft in a hole. three fingers.