Sand or grind all of the paint away from the holes you drilled and weld the tubes in place. We used the HTP MIG200 with a flexible Swan Neck to weld around the circumference of each 1/2-inch hole, making sure to get good penetration between the outer and inner axletubes. You don’t want to simply fill the hole; you want a solid weld. Synergy also recommends welding the outer tubes to the cast-iron centersection with a TIG welder using stainless 312 rod and pre-heating. You can also do this with a MIG welder with pre-heating.
