Over the winter I bought a project boat and it’s almost done now. However, I’m running into a small hurdle trying to install my passenger seat. I bought one of these (pictured below) to install the boat seat on the middle bench of the boat and can’t figure it out. If I install it onto the bench first, I don’t have any room to get the screws into the seat; and if I attach it to the seat first, there’s no way to attach it to the bench. To add some details, it’s a 14ft v-hull; basically a big rowboat with a small engine. 
 

 

How are you fastening the swivel to the boat?

9 minutes ago, Scott F said:

How are you fastening the swivel to the boat?

Bolt through the bench seat with a locking nut. 

Pre drill the holes in the bench seat. Put the 4 bolts through the swivel plate holes. Leaving the bolts loose, attach the swivel to the boat seat. Square up the swivel so the bolts won’t come out if you push on one. It’s a little trickier if the bolts are short, but line up the bolts with the holes in the bench. Put on the nuts and washers. You should be able to get a wrench on the bolt heads and tighten everything up. Make sure to use big thick fender washers to strengthen the bench from the torque the seat will apply.