Chad -- Thanks for the kind comments.
My wife and I intend to use the car more & more for longer & longer trips. And to keep it forever. She simply will not tolerate any discomforts, and recently said the 280SL is now as comfortable as her CLK500 cabriolet.
Over the coming winter my very-able band of friends / mechanical & technical gurus may bring the M130 engine up to a level of performance that will deliver a slightly better HP/pound ratio than a CLK500 (which is slightly better than a new SL500). We shall see.
BUT, I and my merry band of highly-able associates will neither cut metal nor make such changes that than cannot fairly easily be returned to original should the mood ever strike.
As you correctly say, there are two schools of thought here. As I've owned the car for 20 years now, I guess I'm ready to go for some enhancements, or as some might say, "individualizion". But on the flip-side, I also have a lot of respect for keeping things as original as possible...such as my friend, David Pease, has done with his lovely 230SL.
BTW, the inspiration for the Webasto seat massagers for the 280SL came when I drove another friend's new AMG-version SL65. At 600+HP and 740 ft. lbs. of torque a back massage (also courtesy of Webasto) felt pretty good after having been shoved so hard into the back of the seat!
Tom in Boise
'71 280SL 4-spd, signal red w/lt. tan interior, restored/enhanced