Track bar axle bushing sleeve

OK- the hole in the axle bracket for the track bar has wollowed out. Time to drill a slightly larger hole and use a larger diameter bolt. This means that the sleeve in the track bar bushing needs to be drilled to a larger ID. For the folks who have done this did you take the track bar to a machine shop and have them drill it out. The sleeve just laughs at my Lowe's cobalt bits. I am going to use a 0.50 in Grade 8 bolt. I was hoping to use a series of bits of increasing diameters up to 0.50 in. Also do I need to worry about over heating the rubber part of the bushing ? The XJ has a stock suspension so I am using a new stock track bar.

Thanks for any help

1990 XJ

Install a new bushing that has a .5" through hole?