[R129 SL] hardtop sensor malfunction, rear soft top, chip, exhaust

[r129list@mbcoupes.com]

Sorry to be asking so many questions on the first post!

1) Anyone else have the extremely annoying hardtop loose sensor 
beeping incessantly after going over a bump with the hardtop on?  Is 
there a fix other than pushing the button again?

2) Anyone know a good place for inexpensive rear soft top with 
windows replacements?

3) Anyone know of a chip for a 1991 500sl? the fuel injection system on 
the early cars is apparently different.....CIS....

4) I am looking for a good rear muffler with a slightly more throaty sound 
than stock as well...

Any help would be greatly appreciated!

Thanks,

Patrick Greene
Dallas
1966 200 heckflosse
1972 280se 4.5
1981 380sel
1984 380sl
1991 500sl
1995 e320
1991 carrera 4
1972 mgb
1993 f150xlt