np 203-205 adapter for 74 dodges and 440+tranny compatability

I have a 74 ramcharger 4x4 with a 318 727 and 203 and a 74 powerwagon 4x4 with a 318 4sp manual and a divorce 205
I am looking for any recomendations on a doubler adapter. I also have a 78 town and country wagon with a 440 auto and am wondering how to work it into the mix.  Is the bellhousing compatible or the tail housing interchangeable.  If I do drop in a big block into my power wagon is there any stress points that should be adressed with the weight gain.  I also have an 80 ramcharger 4x4 with a 360 auto what would my benefits be for running the 360 sb? as the t-cases will give me loads of low.  My truck is currently running 35 inch tires but i am looking for dana 60's before going to 40+inch tires.  THANX FOR YOUR THOUGHTS AND LIKELY EXPERIENCES.  

I'm running an ORD doubler using a Dodge 203 and 205.  Awesome hardware.  ORD (Off Road Design) is in Carbondale, CO, west of Denver.  Stephen has a great team of personnel and great tech support.

http://www.offroaddesign.com/catalog/doubler.htm

- M2  
78 Ramcharger, 6BT, 518, 203ORD205, D60/Eaton, D70/LSD, 36x15.5 MTZs, armor etc
ASAModifieds.com

Thanks I looked into ORD and also the setup that northwest fab works  offers they also were very helpful.  They also have a really cool reduction box.  You wouldn't happen to know if that 2wd to 4wd tailhousing swap would work do ya...  

I'm not sure...but I'd bet a case of your favorite brew that Stephen would be able to tell you.  He and I collaborated a lot on the all-Dodge doubler under my truck, and he really knows about parts interchangability.  If you call him tell him I sent you (I have the 78 Cummins Ramcharger with the 518 auto - he'll remember) - he'll hook you up proper and he takes the time to explain stuff.  Really great to work with  
- Sam  
78 Ramcharger, 6BT, 518, 203ORD205, D60/Eaton, D70/LSD, 36x15.5 MTZs, armor etc
ASAModifieds.com