Our ramp door hinge selection is limited to just part # PLR1902, which can be welded in place. As for the springs, we have a bit of a selection that you can narrow down depending on the width of the ramp door and the capacity needed. For example, part # M394FR can fit a door width of 67-3/4" to 95-1/2" and has a spring capacity of 185lbs.
I've attached a link below to our spring options. view full answer...