What's a good intro welder for subframe connectors?

A decent 135/140 amp (120V) MIG welder will weld your subframe connectors in just fine. I used a Lincoln 135 on the connectors in my 66 Dart. The problem is, you'll quickly outgrow the 120V machine. I know I did and upgraded to a 180A unit very quickly. I just wish I had started with the larger machine from the get-go

A few quick (maybe obvious) tips are to get the metal clean, joints tight (I've heard the USCT connectors need a little 'fine tuning'), and make sure you're in a comfortable position. Before you weld on the actual work piece, practice on like materials to get the settings dialed in. When welding thicker material to thinner, focus the arc on the thicker side and 'wash' in to the thinner side to help prevent blow through.

Don't forget that the smaller machines don't have much of a duty cycle, so take frequent breaks.