Lot of good questions Howard.
KR is greatly caused by heat. Think of KR as it is.. predetonation of the air/fuel mixture. This happens in a highly compressed and overly hot cylinder.
Going down one or two heat ranges on a plug and gapping down slightly can help greatly. (See Intense-Racing.com website for plug suggestions at certain boost levels). Increasing the flow of the engine.. opening up the intake, opening up the exhaust restrictions. All these things help you flow better, increase power and fight KR.
Boost won't necessarily come in lower in the RPM'* because of how it is programmed in the PCM. However a smaller pulley like the 3.5 will give you more boost which will give you more power throughout the rpm'*.
Sounds like the mod bug has it'* teeth into you a bit. I'd suggest doing some searching and reading up on the modding basics outlined in Techinfo. That will give you a good basis..and should get you moving right along. I also found a call to Intense and ZZP got me off and running by discussing briefly my future plans and how I plan to drive the car versus which mods I would want.
00 Regal GS: All kinds of cool stuff.