Starter clutch woes
 

Hello to all, I have not been here for awhile.
This is for the benefit of those who haven't had this problem. But also help me going forward.

Purchased my 87 in 1994 with 16,000 mi on it and today it has 32,000 mi. After a year or so, it would sound like a few hammers were thrown in the engine when the starter button was hit. Not always but at random times. I would always release the starter button, restart and it would not happen again. Last night I went to start and on 4 tries as long a I held the starter it sounded like a gaint blender with nut and bolts being ground up inside. 5th try and many times after no problem.

From trouble shooting I've come to the conclusion that it's the starter clutch. Something new to me.
So any ideas if I'm correct or not. If I am correct. How many hours am I looking at to complete a repair like this, in someone else's experience. Thanks in advance.