Volvo Penta MD6B VS MD7A

[weephee]

I purchased a boat with a seized md6b engine and I've got a md7a engine in good overall condition to replace it with. I went on line and found lots of information on the MD6A wrt dimensions and weight etc. and it appears that the md6a would be a direct fit with no mounting changes required. Little or no information on the md6b though. Can anyone tell me the difference between the 6a and the 6b. Any additional information I'm missing on doing this motor swap between a md6b and a md7a. Thanks

[weephee]

Let me try this again. Can anyone tell me the difference between the Volvo penta md6a and the md6b. Thanks