So, the A/C issue shouldn't be your only deciding factor. The K Swap is going to run you anywhere from $5-$10K more than a B swap, ESP if you're already running a B motor. But, you will also put out 20 more hp stock, plenty more with the right bolt-ons and a tune. You can keep A/C with a Kswap, it is just a pain to carfully bend and design your own A/C lines. Out of all of the K Rex's on K20a, there is ONE guy keeping A/C. Good luck, with whichever route you choose!