I've purchased a 1993 4.9 300 six and going to attempt to install it into my 63 that had a bad 292 is this possible also has a auto trans to go with it truck has a 3speed now

 

Get a 90s auto overdrive. Youll have to add the trans cross member. And you will anyway if you don't find a way to use the bellhousing mounts as thats the only way the trans was mounted originally.

 

The aftermarket FE "390" tube cross member works for a 300 six.
65 up trans mount crossmember should be a bolt on. You'll have to drill holes in the frame for the bolts.
The stock 63 trans mount cross member may or may not clear depending on transmission choice. You may can work around it.