Dunkirk Empire Tankless Boiler Domestic Coil Replacement

In this video I replace the domestic hot water coil in a Dunkirk Empire 2 boiler after discovering a leak between the coil plate and the cast-iron boiler. This boiler was installed in 2000 and seems to have had the coil replaced sometime around 2009. I obtained a quote from a local burner company and it was between $900 and $2000 (depending on whether the fix was the gasket or coil+gasket.) This quote provided more than enough motivation to kick the DYI process into gear. In the end, I spent about $300+tx and about 6 hours of labor.
Edit: when drilling the holes for the bolts, I mistakenly state 1/8" then 3/8" bit then finally 5/16" bit. The 2nd bit was actually around 3/16".