Timing gears?
 

After a year of procrastination I decided its time to put this YS 400 together and replace the broken 350 in my 70 tempest. I picked this engine up about 4 years ago and took it apart to inspect it. Now putting it all back together I see the timing gear for the crank can go on 3 different ways. There are also a bunch of different stampings on the gear so now I'm a little confused. I took this pic and was thinking these are the 2 marks that belong together. I'm thinking if I get #1 at tdc I would install it this way. Any help would be appreciated. Ty.

NO, that's not going to work. Using the keyway on the crank gear you currently have lined up with the dot on the cam gear, (marked with a 0) rotate the crank gear clockwise and line up the other 0 mark with the cam gear dot.

What he said. ^^^

If you've got the motor apart go ahead and buy a new timing set! They don't cost that much and you may save yourself a ton of trouble down the road.

And your new set will have instructions. ;)

Thanks everyone for the quick replies. Gears and chain are now on. Some date codes on the aftermarket parts installed on this engine are from 1988. The oil filter has a date code of 1990. So approximately 2 years running on a fresh rebuild. Really clean inside. I'm going to install it this weekend and hope for the best.