I have an 89 RS with the origonal 700R4 in and i am interested in a shift kit. It has 100,000 miles on it now so i dont know what you recommend but it still shifts good and firm with what i believe is no slipage. I have herd that Transgo is a good kit, but it is complicated to install. I am not too concerned with price but i am not rebuilding this trans. I am looking for something fairly easy but with good results, but with 100K on the trans would you recommend any form of a shift kit or shift improver kit??? Any imput would be great!