I recently noticed some rot on the lower end of the frame of my garage side
entry door. The house is only 6 years old, but it looks like a couple of
nearby sprinkler heads and some caulk gaps are the culprits. It is rotted
throught the frame, stop and part of the brick moulding.

The damage appears to be isolated to the lower 6" to 8" of the frame and
brick moulding. Threshold needs some finish but seems sound. I think this
can be repaired without replacing the entire frame. I am wondering if
anyone has had experience with any of the following approaches:

1) Carefully sawing out the lower rotted area (beneath the hinge) and
shimming in new stock with screws and glue (easiest but probably least
desirable).

2) Trying to remove the entire door-side frame, fabricating a new one and
sliding and shimming it into place. (Fastening might be a problem but I
will have some access with brick moulding removed. No internal trim.).

3) Just pulling the entire door out, fabricating the hinge frame and
reinstalling.

BTW - I do have experience and equipment to handle the fabrication task.
Just trying to figure out the best way to tackle this.

Thanks in advance.

RonB