You could be in for some bad clearance issues.
The 3L clearance is much less then the 2.5L clearance to begin with and the CAT cams are made for a stock 2.5L (not even an SVT with the domed pistons)
That means they are made for the smaller valves as well.
Half of 3-4mm doesn't sound like much but when your safe working clearance is in hundredths of an inch it can be a mile.
2mm = .08" Offset that by the angle of the valve and it still means clearance is tight. (without the actual valve angle handy a guess would be around .015")
The 3L did change to relieved pistons for a reason. Clearances are terribly tight.
The maximum milling clearance of a stock 3L head is .01" and that is really pushing your luck. The safe limit is .006"
I personally know you can run a small increase in effective lift on the 3L but a 1mm jump is a lot.
