Just my thoughts here... I have been a professional marine diesel engineer for 40 years. We have the parts, the lapping plates, the test stands, etc. to do injectiors on board and I have done many over the years. I still prefer to send them ashore to a professional shop for rebuild. They have the sterile environment and the calibrated test stands to do the job right. Just a few microns of grit will ruin your "new" injector and possibly your engine. What is the cost of a rebuilt injector compared to a total rebuild of the engine, or even a few nights stuck on the road somewhere? I subscribe to doing all that you can reasonably do yourself... then leave some things like fuel pumps and fuel injectors to those best set up to do this work!