t-5 rebuild. self or not

[stng87]

I have a t-5z that needs rebuilt. THe only problem is that it wont stay in second gear and sometimes grinds slightly into 5th. Sounds to me like a synchro-only problem what do you think? With the costs of a a shops rebuild it almost sounds better to buy a new one, neither of which I want to spend the money on though. If i was to spend that much money again then I would rather have it be tward a tremec but I dont want to do that yet either. It seems the best decision to tackle the tranny myself. Who has done this before? WHat are some of the things I may need as far as tools?

I consider myself fairly well mechanically inclined. Ive swapped out the aod for the 5-speed myself also replaced heads etc.