Mopar Forums - general info/help 79 powerwagon

I have a 79 powerwagon w200 with a 318. i belive this year model came with full time 4x4. the people that i bought the truck from took the tranny,t-case and front deffirental off a 87 chevy so the truck has a gm 10bolt axle up front.? iam wanting to put new leaf springs and shocks under it and don't want to order wrong parts. also what is the best way to identify what t-case and tranny it has in it now? this truck is super bad ass i just had a full rebuild on the motor done and cant wait to finish the rest! i guess by me asking all these questions you can tell iam no mechanic and am new to any kinda forum.thanks again for any kind of help or input. will post some pictures as soon as i figure out how.