Well it has run for 20 years and been fairly dependable like it is!
The short answer is: The computer controls BOTH the carb and the distributor.. So BOTH must be deleted from the computers control NOT just one.
That carb you ask about is indeed a good one! However it's problem is the size of the aftermarket air cleaner that must be used with it...in my not so humble opinion.
There is a proceedure called "the nutter" that can be used after installing the new carb that disables the computer from the distributor.. It is a popular proceedure and has been used sucessfully by many Jeepers.
Changing dist types is not a good thing for novices to attempt...
My first thought is for you to look for vacuume leaks. One little vac leak can cause the problems you have described.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />