Guitar Setup Advice (yes its misc & meaningless)

Hi, I think their are a good few guitar fiends about here, hopefully you can help me out.

I changed to a heavier set of strings on my guitar a while ago, then didnt play it for a while.

Coming back to it now, the action seems loads higher and adjusting the bridge is making no difference.

It seems that the neck has bowed foward slightly. It seems I might need to adjust the truss rod, something I have not done before.

I found this guide:

http://www.projectguitar.com/tut/trussadjust.htm

It seems simple enough, but it crucially does not mention whether I need to loosen the four bolts attaching the neck to my guitar body, it doesnt say you do, but I can not see how the neck would move over if I dont?

Any advice greatly appreciated. My guitar has a floyd trem & regular bolt on neck btw.

Given that it has a Floyd trem, I'm assuming that its something fairly decent, in which case I would take it to a decent shop and get it done.