I went to good ol' Wikipedia and found a list of lightships.
It had Lightship D, which it said was built c1854 and served duty until 1860 when it was sunk or captured by the Confederate States Navy.
Lightship No. 8, or LV-8 (Light Vessel I presume) was built in 1855 and originally called the Thomas G. Haight and then commissioned in the US Navy as the USS Arctic and sold to the Lighthouse Establishment sometime prior to 1859. It was sunk by the CS Navy and later salvaged and repaired and used as a lightship again at Hans and Chickens from 1867 to 1877, and then relief from 1877 to 1879.
I seem to remember there being a CSS Arctic at Wilmington during the war. Could this have been the LV-8.
UPON FURTHER RESEARCH
The Dictionary of American Fighting Ships list a CSS Arctic at Wilmington.
It says the CSS Arctic was built at Wilmington in 1863 as an ironclad floating battery. and also a receiving ship for Flag Officer Robert F. Pinkney's North Carolina Defense Force. It was stationed on the Cape Fear River from 1862-1864 (Hard to be 1862 if it was built in 1863) with Lt. C.B. Poindexter, CSN, in command.
The machinery was removed in 1862 to be used on the CSS Richmond ironclad being constructed in Richmond. It was sunk Dec. 24, 1864, in the Cape Fear River as an obstruction.
There sure is a lot of confusion as to this ship. But the fact that the lightship had at one time had the name USS Arctic leads me to believe that perhaps the CSS Arctic and this vessel were the same.
So That's What Happened to Those Lightships. --B-R