So far i drilled new holes and made threads but its way too thin and unsafe. I know i have to get additional metal behind these holes for more support, any ideas on how to make it work?

 

Big *** washer, no less than 3" diameter. Or plate steel.

 

thanks.. but how do i make it work? in other words, how do I attach it so it stay there? i though of makin another hole nearby so i can hold the washer while attaching the seat? how does everyone else go about this?

 

Do you mean hold the washer there while you put the bolt through? Just get some tape, hondabond, glue, a friend...