Yes put it on the seat, I'll add just use 2" fender washers on the bolts, I prefer 3/8" carriage bolts.I wouldn't put any lead in front of the tie rods. I'd put it all on the seat. It might be easier if you don't have a hodge podge of lead pieces. If you buy uniform lead blanks they stack nice on top of each other. 60 lbs is not an issue for the seat to handle. Another option would be to use some sheet lead inside the seat. That's an easy 12-15 lbs on an adult seat.