Engine combinations for a type 1 powered tow car (bus) ?

[Andy]

OK this isn't exactly Cal Look so I've stuck it in here

A friend wants me to help them build an engine to put in their split bus that would be able to tow a small car behind, Austin A35.

Obviously a stroker motor will be the way to go, I am thinking 2110, fuel economy is an issue so what carbs would anyone reccommend,fuel injection may be a possibility.

Would an Aluminium case be a better choice, also what cam and heads would you suggest.

Feel free to chime in with suggestions or experiences