this is a tough one. Hasport has a DC2 with a JRSCd K20a that they are kicking ass with. but the car isnt a daily driver. This I do know. since the K20 spins the opposite way, (the right way) you cant have power steering. im not sure about the A/C either dont quote me on that I think you can not sure. In the end who knows what kind of vibration you might encounter after the swap is done. You might actually hate driving the car.
personally I wouldnt do it. If you really want a k series Id just hold out for a DC5 or EP3 these cars were designed for the K20 and use that as your base. thats my $0.2