My Shin T230 string trimmers are starting to have thier first problems after 3 seasons. The head is starting to wobble because the single bolt that holds it on the outer shaft is stripped out and the hole has widened. My best guess is this is from jossling around in the trimmer rack when driving. So anyway, I got a price of $40 for a new outer shaft. My question is, how difficult is this to swap out? Getting everything off the the outside will be easy enough (head, throttle assembly, engine), but what about the inner shaft? Does it just slide right out, or is it held in place somehow? Thanks in advance.