85 was first year for NA Hydraulic lifters.
Mid to Late 86 was first year for Hydraulic on TD.
An 83 'would' be mechanical if all original.
Check this link to see picture of how to tell a Mechanical Lifter head from a Hydraulic Lifter head:
http://www.vwdieselparts.com/h&m.htmIf it happened while the car was parked - somebody probly mighta played a prank on ya. The shift rods are accessible from under the hood. One is about 8inches long, the other is about 3inches.
They have ball-cup ends on them and just kinda pop on.
They have keeper tabs that are supposed to be unlocked for removing/installing - but if the cups are worn inside- they can pop off pretty easy.
Look down in lower area of section between tranny - firewall.
You'll find them.
The link theman53 supplied has top dog deluxe stuff to rebuild.
But you can get everything to go back OEM style with new bushings, relay ball, and rods for about 20-25 kit on eBay and other vendors - if you need it. And you can buy the rods seperately as well.