91 s10 ext cab trans help

Whats up guys. Im new to the s10 world and need some help. I just got a 91 ext cab s10 with a 2.8 5 speed whin i got it it would not move at all. The guy told me it needed a cluch. After a $180 bucks it drives but no 2 or 4th gear. i called around today . a used 5 speed is $510. what do i have to do to chang to a auto. i have a good turbo 350 will it bolt up????? if not what auto will work. I got the s10 so i could let my 69 camaro sit it out this winter. but i mite need to kick myself in the but. THANKS in advance.