We did that exact thing and it worked fine. Had a stand alone SQL server named “sq01” with a SAN backend. Replaced it with a cluster of two new machines. Gave the cluster the name “sq01” and pointed it at the same SAN drives. If I were to do it again, I would remove the full text search catalogs first, and rebuild them after the new SQL server is installed. That caused us some problems until we rebuilt it all.