Glad to see you got a mill. The little 301cc motor is more then enough power. Ifnyou find yourself pushing hard change the blade. I had a 11 and 13hp motor ready to go but never needed it. I would recommend running the motor for about 3 minutes varying the throttle greatly the n immediately changing the oil, gets rid of the majority of the contaminates quickly. I'm my searching I was unable to find the exact dimension angle iron, I was going to use just equal length stock the same dimension as the short aide however I just called harbor freight feed them a line of ********* and demanded they sell me another set of rails and cross member. However waiting around kinda sucks. I also found that I rarely used the extension as I ran out of log diameter capacity before length, but that's not always the case esp. With my current mill I mill almost all 16'. Messing around with 8' seems like a waste of time.