My very first mopar

Well to start off, im not a MoPar guy. This is my bro-in-laws dream project car, a '72 dart or duster(havent looked at it that close yet). Well unfortunatly he passed away the weekend before Thanksgiving, and i am doing everything i can to keep the car and get it going. He has everything there it just needs to be put together(i hope). The K-member has been swapped, front suspension completly redone to put a 383 HP in it. i need to put the motor mounts on, but not sure how to locate the correct position. not sure what tranny, but the gears are 420's with a mini spool. i probably will ask alot of dumb *** questions, but this site has helped me some already. Actually that was our rivelery, we was MoPar,(which gives me a rash when i get too close) and i am a Ford guy ( which made him go blind when he got too close). Thanks in advance for the help.