yes it can be done. If you can weld together a mounting bracket then your laughing.
all the details are here: actually you cant see the tech archive unless your a member so i will cut and paste the text here:
used to run twin alt's on my 300 (and my previous 200Tdi and 3.9 V8)
on the 300, it's dead easy as you can buy the parts (well, most of them) "off the shelf"
If you use the same type of alternator that the military "wolf" XD's use, then there is an (expensive) bracket available, failing that, do what i did... piece of 5mm plate, drilled to match the 4 air conditioning bolt holes, then get 4 strips of the same 5mm plate, and weld them (in the correct position! ) so that the pulley of the alternator sits in line with the auxiliarry drive belt.
Then get yourself a handfull of the military FFR pullies and tensioners, bolt on, and away you go.
The front cover on the 300 has the castings threaded ready to go for the tensioner and idler pulley, BUT don't be tempted to just use normal civilian spec air conditioning pullies... the military ones come with a knock-on protective cap that keeps all the cr@p out of the bearings... ask me how i know... several months of off road work with the civvy bearings left them all knackered... changed to the mil-spec stuff and they lasted for about 8 years until i sold the 90.
parts needed:
RRC8560 Alternator A1271-50/24V
RRC8761 Alternator A1271-50/24V (these are the 50amp 24v alternators used on XD's)
BH 116131 x2 Bolt
ERR 5870 Mounting Brkt. alternator £74.56
ERR 6005 Drive belt £9.46
ERR 7295 Pulley, ancillary £17.18
ERR 7297 Cover £0.69
ERR 7298 Flinger, oil £1.08
ERR 7387 Tensioner (this IS the same as a civvy A/C one)
FS 108257L x3 Bolts, fixing
FS 110301L x4 Screw, flanged £0.51
G
