is this it?
http://www.unlimitedengineering.com/...ore/13236.html
maybe this dogbone also helps you?
http://www.unlimitedengineering.com/...ore/85017.html

Is the one up for sale for the 3906 or The newer spec trucks or does it not matter ??

I don`t think it matters? as the bulkheads fit both models

Yep, the monoblock fits any maxx truck, you just have to consider the rear dogbone length as what works for the 3906 wont fit a 3905 as such. You can always find something suitable from another brand or model though with a little digging.. :yes:

I'd just like to find one that doesn't cost a arm and A leg. Imho the UE is a little overpriced for a part they do over and over.......

It's a complex 3 dimensional shape machined from a single large billet of aluminium, the metal itself may not cost that much but the machining can be very expensive, especially if you were to get the same thing made by a 3rd party ( that's kinda how you'd pay for the equipment, with high machining costs )..

I'll just have to watch for a used one out there because that's a little high for me and the constant questioning of myself because there are no bodies that long make me shy away from buying one because it looks odd at the wheels.