Introducing new guinea pigs?

Question
I have two 2 month old male guinea pigs.  There are two 1 year male guinea pigs at a shelter near me and I would like to get them.   Is it necessary to quarantine them away from each other for a few weeks (I've heard this)?  How do I go about introducing them to each other?  I have a huge cage so there is more than enough room for all of them.  Thanks!

Answer
yes..quarantining is a MUST...3 weeks at the minumum...different rooms...wash hands before handling your originals after handling the new ones!!

When introducing them.....do so on "neutral" territory..such as the floor or bed.....

good luck

jess