Hood clearance is a problem depending on the intake. K member is ok to use the stock one. Engine mounts are fine to use the stock ones. You will need a different distributor, a different flywheel/flexplate, and exhaust work...or long tube headers and such. I used MAC swap headers and 3" exhaust. I also used the ac delete braket and crank pulley spacer...which I think you would also need. Other than that I would say that I used a MSD ignition and MSD distributor and if you are going to keep it fuel injected you will probably need larger injectors and a larger fuel pump and line because the 351 will require more gas. The heads are exactly the same although the stock 5.0 heads are very restrictive with even 302 inches...much less 351. Bell housing is the same. Same tranny can also be used. Its a fun swap...good luck.
302s have 7/16" head bolts, 351 uses 1/2" so they must be drilled out to 1/2"
Also make sure to check clearances on your motor. I luckly have a plasma cutter and was able to trim things with the motor in the car. My Canton oil pan had about 1/16" clearance between it and the K member, so I had to trim that stock Kmember before switching to my Griggs tubular K.
Also had to trim the pass side motor mount because the Hooker headers wouldnt clear them.
Bellhousing is the same between the 2 motors, so no need to switch unless you want a scattershield.
What kindof heads and intake are you planning on? How much power are you planning on making? That will completly determine what injectors and fuel system you need to run.