My '92 is a bottom breather. Evidently the mfg. date of this bike was during the transaction to head breathing. My stock heads had the breather passages, and the rocker boxes are cast for the umbrella valves, but the bolts from heads to air filter bracket were/are solid 1/2" thread. It breathes through the plastic valve in the cam chest, and out to a tube going up to the air filter. I bought and installed Edelbrock Performer heads that were made to be head breathers, but I just bolted them on. I have often thought about putting umbrella valves in the rockers, and having dual venting, but never found anyone that could give me a definitive answer of possible negative effects of dual venting. Seems like it should work.
So IMO yes, the '97 heads should work. You will need to modify the air filter bracket for the larger diameter bolts.