New to this world!!!

[BrokeTillDone]

New to this old truck world. Just purchased a 1961 truck. I always thought I would build a car never a truck but got to admit once this thing was offered to me I jumped on it. I just picked it up 2 days ago and I can't wait to start ripping into this thing and get it road worthy. I don't know much about the truck pretty much bought it sight unseen but I am very happy with it. Hopefully you guys can help me out through this process. If I ask stupid questions please forgive me as I am not too familiar with the GMC/Chevy world. And now for some pictures.

After a blowout and driving 2 blocks with a flat tire she is finally home:

The tire that gave its life so the rest of the truck could survive:

The bed looks to have been changed. It is sporting a Chevy bed which will get changed out for a GMC bed. Might turn the Chevy bed into a trailer:

When I opened the hood I was quite surprised. It looks like the previous owner dropped a big block in it. I think its a 454 but not too sure. It fired right up and sounds and runs like a champ. Only issue that I was told about is that it will not go past second gear. Didn't drive faster then 10MPH so I haven't tested it out myself.

The only markings I can see at the moment are on the exhaust manifold and the air filter housing:



This is the tranny. From what I have looked up and read it looks to be a THM400 but I could be wrong:


The interior. The previous owner changed out the seat.



I thinks thats enough pictures for now, unless you guys would like some more. I did take a peak at the chassis and it looks a little rough under the bed. I am a blank book at this point any knowledge, advice, recommendations, thoughts, and guidance is very much appreciated.
Sunday will be the first day of tear down. I am planning on removing the whole front, degreasing and power washing the engine and front part of the chassis. I will update this thread with pictures as I go. Wish me LUCK!
Oh how can I make this picture my Avatar?