How do I install a front clip off a 1970 nova 4 door onto my 1951

I have a 1970 4 door nova and I want to take off the front clip and rear end off the Nova and install on my 1951 short stepside Chevy.  Is it very difficult or easy swap?  Can anyone let me know if they have done something like this because I 've been reading about S-10 trucks being the easiest.  I just want to put all the drivetrain on the 51 truck because the straight six motor in the Nova has only 60k miles and a turbo 350 tranny.  I could also update the front clip and rear end to 5 lug.  Suggestions?  

do yourself a favor  use the s10 frame  

I think that is the same as the camaro. We have done a few....not hard but not easy. Also this will track about 2' wider so skinny tires will be needed if you lower the truck or go with narrow A arms or narrow them yourself. This can be difficult or pricey if you but narrow  

PLAN, PLAN, PLAN. You can do it if you really want. Spend lots of time mocking things up and measuring. Where you cut and weld the new frame into the old will determine how low the front end sits. Set it up so all the line-up numbers of the donor still are in effect. Shops will have you sign a release before doing this work because of liability. The welding must be perfect and done by some-one with lots of experience. It is not just your life, but others on the road at stake here. You can narrow the subframe before mocking it up so the wheels won't be an issue. Same with the back frame, but not the rear end.-Church  

The guys above are correct, the Camaro and Nova etc, subframes are basically TOO WIDE for the AD series (47-55 1st series truck frames).

My choice would be an IFS from an aftermarket or if available for low price,a good S-10 subframe.

My 57 has an IFS made by Gary Martz, race car driver and professional race car chassis engineer and builder. The web site is something like martzengineering.net.

I would not fool with all the work involved with doing a Nova or Camaro on a AD truck... not a good fit!  

I have a 72 Nova clip on my 54 GMC 1/2 ton longbed, done by whoever had it before me. The Nova frame is indeed wider judging by the point where my frames "merge"(by about 2" on each side).  But I do not know how the two front suspension widths compare - my clip is not narrowed, I run 245-60 15" tires, I'd say they're pretty wide.  They definitely "fill" the available side to side space inside the front fender - just shy of rubbing.

My original frame is cut at a point roughly plumb with the cab's firewall (the vertical portion).  It's been boxed back for about 18", and the end is profiled similar to what I'd describe as the front tip of a sled runner - the bottom of which is welded in the "drop area" of the Nova frame just behind the point where the steering gear is on the driver's side. At the spot where the Nova frame has "dropped" to its lowest point, the original frame bottom sits (and is welded) on top of it - the inside edges of both frames are nearly flush with one another in the vertical plane. A heavy vertical flange is welded on top of the rearmost part of the Nova frame, and is bolted through to the original frame's side.  I think whoever did this did this flange and bolting first, leaving the ability to get the alignment right, then did all the welding as a final attachment.

My radiator support looks like the original, but its base is in a steel fabbed cradle that puts the engine side of the radiator and support flush with the front flange portion of the Nova's front (smaller) frame crossmember (its core support?). BTW mines a crate 350/TH 350 drivetrain.

The rear consists of a 74 Camaro 10-bolt posi suspended by a TCI leaf spring kit.  Same wheel tire combination on the back, and the inside edges clear the outside of the bedsides by about 1", tight but don't rub either.

Do I like the front clip, yes but there's that seed of doubt about the chance of things breaking -not a comfortable thought as others have mentioned, but hey the silly Nova frame was only bolted to the Nova unibody!

My vote, even though happy with what I've got, is since you're at the beginning and have the choice -would be to go with one of the good aftermarket Mustang II IFS's (I like the looks of Hiedt's SuperRide).

Good luck!