This is a seat I built for the 74 TX650. Made from 1.5mm sheet with a cowl. Front mount is a piece of angle with a 22mm receiver welded in place and bolted to,the frame under the tank mount. The seat is fitted with a single prong mount, covered in rubber tube.
There was insufficient room between frame and guard for fixing bolts, so I welded two tabs to the top,of the seat frame loop, and drilled and tapped them M6. The cowl at the rear of the seatpan was drilled and fitted with grommets. Two Delrin T pieces turned up to fit the grommets so the grommets couldn't be squished too much and then the seat screwed in place using two polished stainless M6 allen's.
There was insufficient room between frame and guard for fixing bolts, so I welded two tabs to the top,of the seat frame loop, and drilled and tapped them M6. The cowl at the rear of the seatpan was drilled and fitted with grommets. Two Delrin T pieces turned up to fit the grommets so the grommets couldn't be squished too much and then the seat screwed in place using two polished stainless M6 allen's.