I thought I answered the question, but here I go again: rebuilding your transmission depends a lot on what is wrong with it. Most AT are OK inside (hard parts) except for friction plates... Rebuiding those involve most of the time replacing the friction materials, which are available for cheap from a lot of transmission parts suppliers (OEM or aftermarket). Even if some transmissions fail beyond repair (metal parts borken, cases broken etc) there are cores available (transmission removed from cars that quit working) and therefore a relatively cheap rebuilt is achieved. In 01M case, a lot of times the planetary gears are locking up and they can't be used anymore. This is a common enough problem that will make the core transmissions pretty rare... A new set of planetary gears from the dealer (I think the dealer is the only one that provides those, except for some aftermarket companies, which sell better parts for more money that the dealer) is around $3000. If one is going to spend $3000 on planetary gears, then for sure $5000 rebuild AT is a better alternative (you can add $5000 in parts alone if you need planetary gears if you do it yourself).
Most AT owners opt for a junk yard transmission, some use AAMCO etc. Hard to say which way is better...
As far as labor from your 30 yrs experience guy: I've looked in the repair manual for this transmission and it is not an easy one. If your guy is not familiar with this transmission, and he forgets/overlooks something, you are out a few thousand $$$ in parts and your car is not working.
I think these are in short the reasons most people will not rebuild these, and good transmission shops are not too eager, either. I am a person that likes to fix things rather than replace (that is the reason I started my post with the AT) but not when parts alone far exceed the cost for a good running unit.
Most AT owners opt for a junk yard transmission, some use AAMCO etc. Hard to say which way is better...
As far as labor from your 30 yrs experience guy: I've looked in the repair manual for this transmission and it is not an easy one. If your guy is not familiar with this transmission, and he forgets/overlooks something, you are out a few thousand $$$ in parts and your car is not working.
I think these are in short the reasons most people will not rebuild these, and good transmission shops are not too eager, either. I am a person that likes to fix things rather than replace (that is the reason I started my post with the AT) but not when parts alone far exceed the cost for a good running unit.