Boy thats the truth.
I put a 6.1 cam in a friends 06 Charger a couple of months ago and have yet to get all the valve springs on.
We kept the MDS lifters but you absolutley need a special valve spring compressor to have any hope of completing the job with the heads on.
Tip: Its a fairly quick job to pull the bumper cover and radiator/ac/fan module off to gain significant working room on a LX.