I found the MCI engines seem to run better than the Pre-MCI versions but I don't like them.
I also don't think it has anything to do with the lift kit.
Have you checked the fuel flow ?
How about fresh fuel ?
I do keep a known good used ignitor in stock for testing just because like you I can't afford to install one and it don't fix the issue. The igniton timing is controlled inside the ignitor from what I read. See if you can borrow one and just plug it in to see if you can ?
They also just about got it right on the MCI's with the updated throttle cable but its always good to check to make sure that throttle plate is opening at the right time.
There are steps in the manual on how to set the cable.
Explains it here starting on page 73
http://products.jacobsen.com/img/manuals/605586.pdf
I usually disconnect the choke cable on the MCI engines because they start so great. You pull the choke and those plugs gets flooded, at least that is what I have noticed.