Mercedes Benz repair: glow plug fuse burning, plug fuse, fuse box

Question
I have a 300D engine working on an original 123 who had a 240D euro version. It was necessary to make all the electric circuits to change the original starting system of that 240 engine to the actual motor that cranks and stop by using a key. It runs great, but recently is burning the strip 50amp fuse, melting also the plastic fuse box. We made a new instalation attending to clean and tight all conections, but we din't fix the problem. It still burning the fuse after a few crankings. The engine uses a loop glow plugs type that I understand are serial connected so that a fault of one of them (in case of shorten internally) not allows to start the engine. That could be the reason of the problem and possible solution? Thanks in advance, Luis.  

Answer
The 240D system will not handle a 300D.
I can not cover your issues here, too much data for this format/forum.

You need to join http://www.mercedesshop.com/shopforum/forumdisplay.php?f=15
where we can exchange masses of data and pictures.

Here are some links that may help.

Engine Electrical:
http://www.mercedesshop.com/shopforum/showthread.php?t=142401