Snapdragon

[Bigwig]

Hi I have a sized md6a on my boat but have found a md5a but it has no gear box my gear boxs is ok and was just wondering if any one knows if I can fit the md5a to the md6a's gear box as would save my self some time in striping the engine down and sorsing parts I no the md5a is a single silinder and the md6a is a twin silinder I have put derv down bors to see if I can unsize it but don't think it will the last owner did not put any oil in the engine as checked it and nothing in it