The 73ft (22m) Motor Torpedo Boat (MTB) 219 was built in Portsmouth in 1941 to defend Britain from the threat of a German invasion.
It has been floated in the docks as part of the next stage in its restoration. Paul Childs, the man responsible for the work being carried out on it, said it had been a "privilege".
"Stage one was getting it out at Tilbury Docks [in London]. We towed it under Tower Bridge from Chelsea," the enthusiast added. "This is stage two. Then we go to stage three and hopefully, when she's finished, she's going to join another vessel that we've got." Mr Childs said the project had cost him £30,000 so far and he needed to raise an additional £30,000 to finish it.
The MTB 219 was involved in attempts to intercept the Scharnhorst, Gneisneau and Prinz Eugen, known as the Channel Dash, in 1942. She also rescued a number of aircrew from downed Fairey Swordfish bomber aircraft and helped sink two German destroyers.
Mr Childs said the vessel had been used as a houseboat for 50 years in Chelsea. Her hull was condemned in 2012 and her owner gifted the vessel to Mr Childs in August 2013.
"We're going to put a wreath on the front, which has been donated," Mr Childs added. "Just to commemorate the guys that actually died on this vessel whilst in service, and the hundreds that died elsewhere in the [campaign]."
Mr Childs said stage two of the restoration in Bridgwater was likely to take a year, but the vessel could stay in the town for longer. During that time he hopes to host opens days and encourage volunteers to lend a hand with painting and maintenance.