W114 --> W123 engine swap
 

I have two 240Ds. One is a 1974 240D, and the other is a 1982 240D. The body of the 1982 is beautiful, but the engine desperately needs a rebuild. The 74 is rusting quite a bit now, but the engine was rebuilt around 30k miles ago. How complicated would it be to switch the engines from these two cars? Is it a reasonable thing to do?

Thanks!

The accelerator linkage & transmission controls can be a problem! So can the oil filter as they are in different locations. Also the glow systems are completly different. Also mounting the A/C compressor & making up new hoses will be a chore.
The intake & exhaust manifolds are also very different & will need swapped.