Oh...my bad haha! After driving the kelisa these few days, I think K3VET is a good idea. Having more ponies is better than having less even though hardly gonna fully utilised it. The feeling of leaving bigger cars behind or those that want to bully small cars with such face    is just priceless

Gonna go check out the price and see since u did mention not a cheap conversion. Some say better to just BOT the stock engine which is cheaper and hassle free, no need endorse. But I think the outcome would be different than K3VET.
What do u mean by overflow? Running to rich?

IINM try checking spark plug and spark plug cable. Other than that I not so sure. My car only choking in the morning during cold start. But is fine with me since the drive is smooth.

Check fuel filter too. Not sure the price. 

change engine. LOL

service the carb is cheap... heck i think u can do it urself too....

and ask them to retune the carbs too...