Just thought I would post here about a positive shopping experience with DB Electrical.
After replacing the batteries in my X, I did find that I was only charging at the high 12v range and low 13V range. I decided to be proactive and get a new alternator... A stock size replacement from Advance Auto parts was $200 for 110 amp capacity..

Doing a search on ebay and google I found this eBay Motors: FORD 7.3L EXCURSION HIGH OUTPUT ALTERNATOR 00 01 02 03 (item 370155097392 end time Mar-07-09 06:01:48 PST) A 200 amp replacement alternator with no core required for the same $200 plus $15 shipping
the company website is DB Electrical Starter-Alternator

Just wanted to say I ordered it on Sunday and had it UPS 4 days later, A day earlier than estimated delivery date... I found several reviews of their products on various forums and sites all said good stuff... Plus they give ya a free high quality fitted baseball cap too.... They have a 220+ version for an extra $30 but really no need for that. you will rarely hit the max demand load on the alternator and the Idle amps are what are more important....these are 100-105 amps at idle. the pulley is just slightly smaller than stock and it worked with the stock belt though I may drop one size in belt when i change the belt next time.

My plan is to add one or two deep cycle optima batteries under the truck and use DB's 200 amp isolator. then I will connect future accessories such as jumper cable quick plugs, winches and inverter to the deep cycle batteries...
At some point I will get around to doing a load test to confirm the claims of 100 idle and 200 max amps.. then will post results here...

 

Don't forget when doing these high power upgrades, you need to do the big three as well. I'd say no smaller than 4ga for your alt, but since your talking about a lot of load, 1/0 isn't a bad idea either. I did a H/O 230 and 1/0 was recommended, it's also a decent idea to fuse the new lead.

 

yeah I got some 0 gauge welding cable laying around here,, just got to get more terminals

 

Watching this with interest

 

DB electrical is literally about 2 miles down the road from me. GREAT bunch of guys that make some quality products that they stand behind.

 

I'm going to second their business
My battery light has been going on and off for last week or so, was able to check it out on sunday, determined the alt was shot, ordered the 200 amp alt and according to my receipt it was at 11:43PM Sunday night, by 9:30 Monday morning I had a tracking number emailed to me and it's out for delivery now...
all that plus a bigger alt for less than a replacement from the local parts house...

 

how doing a pair of alternators like this. I have one for the factory location and electrical, and the other for the stereo.

 

Oh, Just for your info, the 7.3 has a factory setup location to add a second alternator too. an additional belt and pulley get added to the crankshaft pulley. That sure seems like a lot of side loading on the bearing of the main alternator.

Glad other people found my post useful too..

 

Just remember that the dual alts on the diesels uses the pcm for the field wire. The side load on the main alt isn't that much. The company that I used just came out with a 300 amp alt for the diesels and it puts out about 175 amps at idle.