I have an underpowered M127.984, 135 hp engine in my 1963 220 SEb Model 111. I have the opportunity to buy a 1969 M130.980 or an M130.983 including transmission. The question is will either engine be a slip in replacement without modification for mine? What is the difference between those two fuel injected engines? Is there a difference in transmissions and their connection to my driveline universal as opposed to my 1963 DB4?