Alarm bells went off for me when you said you bought a DT250 B pump ,
and thought it would be the same as your DT 360 .
I went and checked in my parts books .
Oil pumps are not identical between DT 250 A & B , or between DT 360 A &
DT 400 B , let alone between 250's and 360/400 .
For a start , the worm gear is a different pitch between 250's and 360  .
Best bet is to be patient and wait for DEET to do his work .
He's pretty quick on the turn around .

so much for my Partzilla cross-referencing! 
Now I have a real reason to find and buy a DT250!

Unfortunately , that's a problem that has occurred after the parts manuals
went to microfiche . In the case where 250 and 360 might be on the same
Fiche , there is no identification of which part fits which bike .
That's a reason why  pistons and rings for sale on Ebay , can be tagged to fit
both a 250 or 360 , when patently they either fit one or the other .

Busy last 10 daysYamalube pump to Mr. Deet, in the meantime I obtained a used pump with proper validated output so I thought I would put in a gal of 32:1, bleed and adjust pump and give her a few kicks. started up nicely, rode nice around the hood.Timing seem close enough?kickstarter only has ~1/2 a turn preload. Works fine and stays parked properly but I get the feeling it needs a full turn added.  I think I can do this with clutch cover off, what do experts think about preload?  1/2 turn or 1.5 turns?I am going to wait for fresh pump before going for a real ride, but feeling good after first ride that was way nicer with a fresh top end and proper jetting.  I used every tip provides so hopefully this time I get a nice reliable peice of history!Busy last 10 daysYamalube pump to Mr. Deet, in the meantime I obtained a used pump with proper validated output so I thought I would put in a gal of 32:1, bleed and adjust pump and give her a few kicks. started up nicely, rode nice around the hood.Timing seem close enough?kickstarter only has ~1/2 a turn preload. Works fine and stays parked properly but I get the feeling it needs a full turn added.  I think I can do this with clutch cover off, what do experts think about preload?  1/2 turn or 1.5 turns?I am going to wait for fresh pump before going for a real ride, but feeling good after first ride that was way nicer with a fresh top end and proper jetting.  I used every tip provides so hopefully this time I get a nice reliable peice of history!   

Sorry for last post - I was a mess without my glasses!

one thing I learned was that I needed to ground the negative side of my timing light to not only the 12v battery I used to power light but also to the negative side of the bike too. 

Congratulations on getting it running again. You worked hard and dilegently to get everything right and it sounds like mission accomplished. Well done!

On the kick start, I'm glad you asked that question and I hope someone who knows will respond with the right answer. The preload was (and still is) a worry to me as well and like you a half turn seemed a little less than what it should be but I was afraid that going another whole turn would risk damaging the spring so I left it at a half turn. 

Just keep in mind that if you do decide to go another round , if the spring can't take that much tension and breaks, you'll have to split the case halves again in order to replace it.

thanks Jack, it pulled really strong and didn't seem to be pinging like before when I was unknowlingly running the #150 mainjet along with other issues.   It just sounded and felt better all around.

yes, i dont desire to split the cases and await input from those who know best whether another turn would bust the spring....but the lever doesnt seem to have the bouceback as i remember 

Yep, I feel the same way about mine, return seems a little weak. 

If the kicker returns It should be correct, the ignition timing has to be checked with a dial gauge, the timing light test will just tell you if the CDI box is malfunctioning or not, I reccomend a setting of 2.6-2.8mm btdc depending on your fuel quality

Not sure now but you 'might' be able to ramp the spring up a little at a time by moving the stop around a notch as by memory there's a dot to line up but if you ignore the dot & go a little more as won't take a full turn of preload. Take what i say lightly as could be wrong & not been in one of those since for years at work.
www.partzilla.com/catalog/yamaha/motorcy.../dt250a/kick-starter