273 for early A

That 340 crank is going to be overkill, sell and aquire a 273 crank as the EGGE pistons will already be balanced for it IIRC. Your 340 crank will support the 998/999 convertor but the balance charge will be more than the cost to machine a 273 crank for a 998 convertor. 302 heads are semi closed chamber, and your egge pistons are pop ups: Run the correct head gasket for that interference combo!