What year and size is the engine and what type of vehicle. If its a 216 you may want to consider upgrading to a 235 or 261 if you want to do a simpler change out unless you have a V-8 in your vehicle. Again need more info.
If you have a older inline 6 from up to 1962 then it will be easier to remove the clutch housing with the motor unstuck. Believe me I know, I was not as fortunate and had to remove everything and drop the crank with the flywheel to get to the 4 hidden bolt behind the clutch housing.
My advise is to you is to try and free up the motor and do a compression check and look things over. If you can not free it up then your are looking at a complete tear down. If you tear it all the way you can take the block to a machine shop and have it hot tanked, inspected, and magnafluxed to see if you can rebuild the block. If this is an inline six they are not cheap to rebuild like a small block Chevy. Before you waste a lot of time and money its best to figure out what you want to spend and if your going to replace it with something else.
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my sweet ride." -Amen
56 Chevy 3100 
