Welcome Van, I have very little personal experience with the F's but love them for what they are. I have seen them with a 6/354 Perkins conversion which was a good conversion. I would imagine a 6BT or even an Isuzu 6BD1T to be suitable donors for one. Hope you find out what you are after and hang around here, lots of knowledgable and friendly people who are quick to help.
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