+1 grind press swap the stems, I have done it a couple of times, or use an XS750 "standard" fork AFAIK it is plug and play but the tubes are a bit longer (1"?) No matter how big the fork IMHO the early frames are still "whippy" compared to the better braced late frames.
So as always when modding, the whole bike should be considered in your "goals"
Back in the day road racing my CB900F at Road America a guy had an H2 750 that really made some horsepower, he had grafted some big wing? front end on the notoriously flexible H2 frame, I'd pass him every corner he'd take it back every straight. He finally tried to match me through the corner, I last saw him headed out into the woods riding a tank slapper.