Not sure what you mean by "all the little parts".
When I got my fuse upgrade, the unit came as one piece, no little parts. Installation is pretty quick and easy, took me about 15 minutes in the dark. A search should have provided the how to.
To install, remove the two phillips head screw from the leading edge of the fuse box (I can't recall off hand if there are two more further back or not). Once the screws are out you have to remove the leading upper edge of the box, then the whole fuse panel lifts out. Raise it high enough to remove the screws which retain the pink and white (or are they grn and white, or are they both colors - I can't remember - help me
) wires to fuse 15.
Now, starting from the left fender liner, forward of the outer wall, lay the fuse link on the fender liner. Feed the wires through the wall along some of the harness that passes through, then go into the front of the fuse box. You may have to cut off one of the rubber plug nipples from the rubber panel on the front of the box to get the wires through. match the wires to those you just removed the screws from, they will be the same colors as the factory wiring, gang them together and reattach to the fuse box in the priginal location. Disgard the fuse from the #15 slot and use a marker to line out that fuse on you map card under the lid.
Make sure all the rubber blocks are inserted correctly, reinstall the upper leading edge of the box and then mount the top layer. Now the lid can be closed and the only thing you need to do is secure the stup fuse compartment to the fender liner using self taping screw, probably a #8 screw 1/2 inch long will do the trick.
Hope this helps.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.