at what point do I swap discs (4 disc rip)

[diamondview]

Hello all

I am new to the ripping game
(just got a ps2) and successfully did
Simpsons - Road Rage

tried my luck with Colin McRae 3 and while I can
boot disc one with no problems

when or how do I swap to the other discs when trying to access another stage in another country ??

any help appreciated

frustrated
diamondview