amp/pre amp utilizing two integrateds


So before I try this connection, I'd like to get a little input on the do's and don'ts. I am considering using a Rega Elex R as a pre amp for my Mac MA6450. As simple as the connections look and sound, I obviously don't want to ruin anything, and I have not attempted this before.
Pre amp output from Rega, to Power Amp in , on the Mac. and then there's the INT/EXT switch on the mac?
What mishaps could arise from this connection? TIA
128x128twinsdad
I presume the EXT will separate the preamp section from the amp section in the Mac! Do you have the owners manual?
It does exactly that, but which setting do I use? Am I safe either way? I have the online manual, and it really doesn't say much about it, only the back panel diagram.
I would think that you would want to use the EXT switch so the amp section of the Mac is like a separate power amp. Throw that switch and see if the controls on the Mac stop working. If they do then you can use the Rega as the preamp. What position is the switch in now, INT or EXT ??