I re-powered my 1541 with an ECH23. Here is the thread.
http://www.onlycubcadets.net/forum/s...ad.php?t=17159
I decided to go with EFI after reading so many posts with people having trouble with their carburetor equipped engines. It reminded me of the 1980's when automobile engines were such a pain to keep running with all the stuff needed to meet pollution standards using carburetors.
The latest EFI series from Kohler use pretty inexpensive parts. The computer module is around $120. A few years ago the same part was over $300.
The motor runs great all the time and uses a lot less fuel. I would use an ECH engine if I had to do it again.