From what I've read, the 318 & 360 magnum engine swaps are cheaper than the Hemi swaps. The early (OBD-1) magnums are said to have the easiest wiring, if you want to keep the fuel injection. These engines can also be swapped to a carburetor if desired.

G3 swap has been done a few times,
Mounting it in is the easy part,hardest part is deciding on Carb Vs Fuel injection....stay away from the 545 trans too many issues better off with a 727 518/46RH or any manual trans
http://bouchillonperformance.com/inc/sdetail/669/742

A316/360 Magnum, is an easier swap

Easiest fuel injection and overdrive swap would be from 90-93 pickup or ramcharger. Dakota can be used but needs transfer case or front axle swap.
Next easiest is 94-97 but need more electrical interface work and either transfer case or front axle swap.

In any of the above you lose full time 4wd transfer case. Up to you if you want to swap the front axle for something with locking hubs which will necessitate a matching rear axle...

Best thing to do is find 1993 W150 or W250 360/518 4wd truck that is rotted out and cheap.Everything you will need is there.W250 will have Dana 60 which is a plus.

Best thing to do is find 1993 W150 or W250 360/518 4wd truck that is rotted out and cheap.Everything you will need is there.W250 will have Dana 60 which is a plus.

That is exactly what I did. Bought a totaled 93 Ramcharger and put the drivetrain in my 75 Trailduster

Id find a running rusty 91-93 truck. Use the engine, trans, transfer case and maybe driveshafts ,then swap 80-93 knuckles and eliminate the full time garbage.

Just to clear some things up:

Your targets for donors are 1992 trucks/RCs with 318 or 1992 trucks/RCs with 5.2 r 5.9, The years prior (1988-1991 for 5.2, 1989-1992 for 5.9) were TBI and those harnesses are quite difficult to transition to work on a magnum engine. If you want to keep the fuel injection, the fuel tank really should be acquired for that application- it will make things easier for you. Even the cab harness is different on 3 major wire locations comparing 1991-1992 for example. People used to use 1992-1995 dakota harnesses for this swap alot back in the day, but not as easy as full size harness. Summary- you need the engine, cab and chassis harness

Transmission options if overdrive is required range from 1990-1995. Most 5.2 a518/46RHs were lockup but (1992s were for sure in light duty trucks) but 5.9s are hit or miss til 1993 on lock up. 1994 -1995 will be lockup.

OBD 2 started in 1996 and things get more complicated after that from a wiring standpoint.

Axles can be anything from a 4x4 from 81-93 and for rear axle, from a 2wd from 1985 up. Beware of the 9 1/4 HD. Used on light duty 3/4 ton trucks and everyone calls it a dana 60- people dont bother to look, nor do they care when selling them

Cam and a 4 barrel will make a 5.9 magnum act like a 5.7 hemi. Best years for 5.9 magnum are 1999-2003. The camshaft was changed to the 1998 Grand cherokee 5.9 limited cam. There is no best years for 5.2, thought the 1992-1993 5.2 exhaust manifolds had the 2 1/8 outlets and are thought to flow better

doing a 5.9 magnum should be cheaperthan 5.7. I cannot get a 5.7 in Maine for less than 1900, while I can get a 5.9 for 700 with less than 100k if patient. But the 5.7 needs a special aftermarket ECM harness if going that way that is at least 1000 extra, plus oil pan, motor mounts, oil filter adapter. 5.7 has much more potential but at what cost?

Yes, hit or miss whether it was lock-up. Balance is uniqur to 5.9 magnum if I understand, so you need the flexplate/balancer for your year engine. To make it more complicated, sometime during the engine run from 1993-2003, they stopped putting weights on the flexplate and put them on the convertor (or vice versa, it gets confusing). Bottom line is get everything you can with your donor engine and know what year it is