Wat system r u using to mount your alternator cause I'm looking into doing a similar system with my dart because of the motor plate I'm using to mount the engine instead of motor mounts.
As with everything else on the front, I will custom make it from .500" 7075 T-6 Aluminum, In your case using a full motor plate, I have seen guys machine the adjustment slot into the plate and mount directly to it which I will basically be doing also, if you get that far all you will need is the correct spacers to align everything. I did a quick inter-webs search and found this, since your running a Big Block you have another option, like a low mount alternator kits for Mopar engines that utilize the timing cover as the mounting point ...that might be a better and easier way to go. Here's one I found through Mancini for $102.00 the only draw back I see is you have to run a Mini Alternator.