Typically one side had a hinge and the other side is secured wti a couple of bolts threaded thru the guard and into nuts welded to the backside of the trailer rail.

Here is a photo of mine. I like it and it looks bad azz, but I am always a little nervous backing it into the water when the boat is already at the dock with all of that aluminum sticking out there 5-6' past the bunks.

If it was me I would not weld it onto the existing frame. I would bolt it on. That way you do not have any issues with rust.

PremierPOWER - where did you get your prop covers?

I remember at a race that a team got rear ended on the way down and the drive guard made it so that they could not get the boat off the trailer!!

still beats diggin the drives outta the bilge!

I think that it was Hot Duck.

I got a removable drive guard on the trailer that I had built for my Top Gun. I removed it before ever launching the boat for the first time with the trailer and never put it back on.....it's been in my attic for the last three years!!!!!!!!!:D:D

here's a few of mine to give you an idea......I wouldn't have a trailer without a drive guard.