I'm running a t18/d20 in my YJ. It needs a rebuild but still keeps working so I keep not pulling it out to rebuild.. lol
I'm pretty certain that the Jeep t18 never came with a d300 at any point, but if they are already together and working its fine. A Ford t-18 would easily adapt to a d300.
The Scout case will work, but doesn't use all 5 mount bolts like the d20 does. It would be fine for a mild rig, but I know Tommy swapped the Scout case into his buggy after I bought his tera-low d20 and promptly broke the case in half. After that he ponied up for the AA adapter and installed a normal d300.
BTW, I dig this rig. I wish I could talk myself into buying Dan's m38, but I'm convinced I won't fit. My wife gave me the stock answer when I showed it to her. "Sell the boat" :blah: