4X4 application?

I'm curious if there was ever an oil pan made that would clear a front diff. Looking at an ideal engine upgrade for the 2.8 in the first generation Troopers. Since it's got a 60 degree bellhousing the 3800 becomes an obvious candidate. The 3.4 is almost a direct bolt in and has been done many times, but I'm of the opinion that the 3800 would actually be a better motor. Only issues I see needing to get clarification on would be if RWD exhaust or headers are available and what about modifying an oil pan, would the pickup tube need to be modified? Any other suggestions are appreciated. We've gotten ahold of a '79 Buick Regal with a carb'd 3.8 that we're planning to use as a prototype. I'm sure you guys will all yell about how we'd be better off with a later model EFI motor, but carb stuff is already there and so simple to wire up.