There is a plug-in connector that plugs in on the top, so connections are alright in that respect. I don't know exactly what year, I think it was 2000, where these clusters were made to be more resistent to tampering. So the '98 and '99 wiring/design I assumed to be the same, and it would hook-up without problems, thats why I bought the '99 cluster.
i remember you mentioning that a while ago on here where you upgraded your cluster, thats why I assumed the 98 and 99 should be good to go. I guess I''l find out soon.