I want to start off my first post by saying that this has got to be one of the most helpful forums out of any I belong to. I stumbled across this forum when I first even considered buying my Datsun and there are so many knowledgeable people on here it's amazing. So thank you all in advance for the advice I've gotten before I became a member.
Now on my intended post... A few months back I purchased a 1964 320. I had seen it on Craigslist and thought what a cool little truck it was, I had never seen one before. I am a huge fan of Datsun/Nissan pickups. Had a couple different ones I drove in my high school years. Was told by the guy I bought it from that he basically bought it the way it was. Engine pulled, cab unbolted because previous owner couldn't figure out how to pull the engine with out doing so. Parts truck came with but everything was basically complete, missing a few parts but wouldn't take much to get it back together. Now several months later, I'm finally getting ready to tear the engine down. I was under the impression that everything was original being and I had the E1. I'm glad I started cleaning everything before ordering parts that I can't find. Turns out, if I'm not looking at something incorrectly, it is a j15 engine (RR of block just under cylinder head has J15 and like 5 or 6 other numbers) No wonder I've been having such a hard time finding parts. Has from what I can tell the original column shift transmission. Now I don't necessarily think I was lied to about the truck, I just wish I would have known what I was getting and what to be prepared for.
So that all being said what are some options I can go with? Obviously the J15 engine and E1 transmission won't line up. I know this because I held the trans up to the motor and the flywheel is too big to even fit in the bell housing. Took flywheel off, only top 2 bolts line up. I didn't know if there are some options that I can maybe change some things to make them work together or if I should just try finding a trans that will bolt to the J15? Also doing some Google research, shows that the J15 was put in the 521? But parts research shows either the J13 or J16 was the only options. I'm so lost on where to even find parts, every time I search "j15 engine parts" it brings me to forklift websites.
Is there hope for me to get that engine put in my truck without a ton of Frankensteining something together or should I try a different route all together? I'm not looking for a show room quality restore or a totally custom rat rod, I just want I nice little truck I can drive to work and stop spending $100 to fill my truck every paycheck.
Thanks in advance for any ideas and info, it is greatly appreciated
Squatch

Welcome aboard!

Wow, that's a hell of a first project. Let's start with this: I can't imagine a 320 as a DD. It's underpowered and balky, and I wouldn't plan on great mileage, especially considering age, wear on the engine, and the likelihood of getting the fuel consumption (mixture) exactly right. Even once you get it to run and drive, steering, braking and other bits are hard to source, and rubber parts are unobtainum.

With that said, a J15 is just a hogged-out J13. You'll have a few options: Source a J13 trans from a 520-521 truck (but you'll have to convert to floor shift), source an E1 engine (rare and will need a rebuild), or swap the whole enchilada (people have used the A13-14-15 drivetrains in these with success). None of these options is economical, and getting a column shifter to play nice with a later drivetrain may drive you to drinking.

I wonder if you might not be better served passing it along to a 320 enthusiast and find a running 620/720 to tool about in (FAR more functional, and parts are more readily available).

I am actually thinking that exact thing. I was not prepared for all of this. I've had project cars/snowmobiles/ATVs in the past. They all came with their own issues and frustrations but nothing like what I've got with this. I don't want to give up on it but when it comes to a limited budget and very limited parts availability, I think I may be in over my head. I will continue with my research and explore some options, thank you for the suggestions.

"Gotta know when to hold'em .........know when to fold'em ".............dah dee......dah..dah..dah

You basically need some of the E1 parts to fit up the J15,
Back engine plate because of the bolt circle shape for the column shift transmission,
A column shift clutch plate and clutch cover/pressure plate.

The J15 flywheel might work. The E1 had a smaller round clutch plate and cover.
If the J15 flywheel fits it might work if drilled for the smaller clutch cover.
I think they all use the same ring gear on the flywheel so should have the same flywheel OD.

As far as engine parts look for J15 forklift parts.

My first car was a L320. I used it for a daily driver for 4 years and went all over in it.
It is a little workhorse as long as you are not in a hurry and don't exceed max speed.
It will carry quite a load- we used to take two motorcycles out to the desert to go riding.
Just be prepared for everyone to be looking at you as they pass you !