4x4jimbo

interested in puting a 12v cummins in place of my 318.its a 85 ramvan.i took the 318 727 and np205 out of a 85 d250 3/4 ton. this has ben in for years.everythings converted already .it has 3.73 10 bolt gm axles w/lockers being the front shaft is on pass side.i already know im going to have to beef up the suspension and put at least 3/4 ton axles,get new driveshafts made.etc.
ive found a few 12v attached to 727 and np205 t cases. i need to know wat my excursion is going to be on #1 trans crossmember .will i have to move it? #2 engine mounts. are they the same? do i need conversion mounts?or should i just weld in the crossmember off a donor truck?
i kno im going to have to finagle the doghouse and firewall.and im pretty sure i will have to do something with the radiator or a electric fan.
any help is appreciated


thank you
jim