Swapped out the cap but not the rotor?
There is also a screen on top of the distributor shaft housing that would get clogged/rusted up after moisture intrusion on the Vortec's. Check it, you can punch it out
or replace the housing.
Got a couple Crossfires still , son is on a 2001 ZR 600 I kept since new.
We have his 79 ET300 twin special, him and Mom do some vintage races on it still.
The boy has been driving sleds since he was 3.