The rear keel roller is in a fixed position and its primary use is to assist in launching and retrieving the boat and not as a support roller when trailering.

This roller tends to take the hardest of knocks being the first and last point of contact with the boat, so a good secure mount to the trailer is required.

Fit the roller loosely to the U bracket (either MK10 roller or 6" (150mm) self centering/cotton reel roller and corresponding U bracket) and position the bracket centrally with the rear cross member. Angle/tilt the U Bracket back to allow good clearance between the roller and the crossmember - around 20 degrees from vertical and 5-10mm gap is ideal.

Tack weld the U bracket in position and check the bracket is level with the trailer.

Measure between the bottom of the cross member and the rear underside of the U bracket for the U bracket brace. Cut a section of 50 x 6 flatbar to fit and weld in position.

Fully weld the U bracket and brace to the cross member.

The U bracket brace plate can sometimes be used for fitting an outboard motor support brace. Drill an oversize hole centrally in the brace plate to suit the outboard support brace dimensions.