I have read where all 4 wire 02 sensors are the same ...only difference is the length of wire..so is there any problem with splicing before the connection? Any concerns to be noted in splicing the wires?
I am looking at Bosch universal 02 sensors.

there was some debate a while ago on contour.org about this and whether they were different or not. Some stores list the same part number for all of them and some dont. Your probably fine if you splice them, although if you already paying the $70-80 for a Bosch spark plug, why not just buy the whole unit?

Buy the whole unit - its worth it!