I've been in the middle of an LS1 swap for far too long, but the average vette owner can tackle it with no problems....I just tend to be slow with my projects. Look at the Build thread in my sig for starters. Also, I hate to point you to CF, but the
Epic LSx thread has TONS of info, As Gene said. You could read the whole thing (I did), but your best bet is to just search it with the question you have. Almost all questions and options have been answered. Only wiring seems to lack there, but that's because the
Conversions and Hybrids Section of Ls1tech.com covers the wiring pretty well.
Here's a few partial answers to some of your questions:
Yes, a Muncie will bolt up. I believe the bellhousing works, but misses a bolt or something. For a clutch, you need a conversion clutch package for proper fit and splining. I believe Mcleod (sp?) makes one.
I haven't worried about this too much because I went with a 2000 Firebird LS1 and matching 6 speed. As it's been said, Fbodies have the trans in the conventional location. In fact, all LSx cars (rwd ones) have the trans in the conventional spot Except the vettes.
Motormount plates are a dime a dozen these days. I spent $100 on mine 2 years ago. They can now be easily had for $50. There are multiple designs, but most are simply plates that adapt old 3 bolt motor mounts to the 4 bolt mounting points on the block. They also typically set the engine (bellhousing mounting flange reference plane) 1" forward. You can get 1" back mounting plates (stock location), which is what I run, but there are advantages and disadvantages to doing either. That you would have to determine for you. Also, don;t just go with the cheapest. I would go with a pair someone else has used in your applicaiton. There's a few floating out there that don't compensate for the thickness of the plate, which will not allow alignment of the motor mounts to the frame. The thicker the plate, the lower on the plate the old chevy mounts have to bolt up. I can recommend Speedhound plates, but I believe he went out of business.
Yes, the engine fits rather nicely. It's actually dimensionally smaller then a SBC, but only just. However, the water pump needs to be "modified" slightly. The stock heater ports need to be either redirected or plugged and taps put somewhere else. Also, a straight water neck needs to be installed on the intake. These need to be done because they all would be going into the Upper LCA on the passenger side.
Accessory locations are also important. I don't believe C5 acc locations work in a C3 frame, but I could be wrong. Either of the above listed threads go over what acc fits, what doesn't and why. F-bodies work the best, but the A/C compressor needs to be moved up high (brackets are available). I don't run A/C, so this wasn't a concern for me.
Donors can be trucks, F-bodies, vettes, anything with an LSx. Some require more work and just depends on your specific goals, skill level and needs.
And just for nomenclature, LS
x refers to LS1,2,3,4,6,7,9,A, etc. LS
X refers to the GMPP LSX iron block.
Goodluck with the research and the swap. It's a lot of fun :beer: