Complex sentence: Jeric & Walsh worked together on guitar parts, but Jeric ended up splitting as well in the spring of 1968, replaced by Ronnie Silverman, who was now discharged from the service.
Split into simpler sentences: Jeric & Walsh worked together on guitar parts, but Jeric ended up leaving as well in the spring of 1968. He was then replaced by Ronnie Silverman, who had been discharged from the service.