Update:
I used a kreem tank sealer kit on my tank with the pin holes. I used aluminum tape over the section that had pin holes. The instructions clearly said duct tape will NOT work. However, aluminum tape worked well and held up for all three steps in the process. Rust eater. Metal prep. Final sealer. I plan to leave the tape in place because it is so adhesive I'm afraid it will pull the tank liner if I peel the tape off. I have tested it for leaks and all looks good so far. Time to get it on the bike and resolve the other issues noted in my previous posts.
youtube.com/shorts/jEPh9XazYuo?feature=share8
 

The best is Caswell although after a few liners, the soldering method works well and no liner needed. The Kreem is going to go bad unless you use non ethanol fuel.

Good to know. I do use non ethanol fuel exclusively on everything, including my Malibu. My 400 has Kreem liner done by the PO and it's going on 9 years now. I shouldn't have said that. Probably jinxed myself. 

Ok, so 2 months later I finally got around to more test riding the DT360A.  I put the Bassani expansion chamber back on it. I had previously swapped it out with a stock exhaust that I had from my other 360. I burned out the chamber and I opened up the silencer. I opened up all the tiny holes that were closed off with carbon on the insert, and then repacked it with the proper fiberglass.

The bike was hard to start, and felt low on compression. It finally started by holding the throttle wide open. The amount of smoke coming from that clean exhaust pipe was unbelievable. I rode it around my property for about 15 minutes. It was blubbery and wouldn’t rev properly. It took about a half hour for the smoke to clear my yard after I shut it down.

I am quite certain I dislodged the crank seal on my previous test ride like Morley suspected. It went from running great to instant smoke show on that last ride. I will order all new seals and have at it once the parts are in hand.

Confirmed!
Morley was right again. Popped the crank seal out exactly like it did on my other DT360A. It actually bends the fricken steel retainer. New seal is due to arrive on Tuesday, but I forgot to order new gaskets…..such a rookie. youtube.com/watch?v=-ag6f_QkmYY&feature=shared

Had to go back & look where i said 'that' & solved it.
Post #48 but i'm not that clever as looks like i decided exhaust blockage.
Happy to be wrong haha & still things to learn.

Seal force bent the steel retainers back?

cliff

Evidently yes. I don't know what else it could be. Both of my 360s have had this exact same thing happen and bent the retainers in similar fashion.

The new crank seals arrived early! So I have replaced the popped out right side seal and will tackle the left side tomorrow.  I could see that pressing the seal into the bore was going to be tricky, so I made my own DT360A right side seal setter. It worked great. I had to do the final set with my mini rattle gun because the crank would rotate too easy using the little ratchet. Believe it or not, I had everything I needed in my cabinet drawers. I throw nothing away without stripping it of anything usefull. youtube.com/watch?v=JDq0PwSc9AY&feature=shared

youtube.com/shorts/4USk-V55UWw?feature=shared

New crank seals are installed and I fixed the locked up clutch. It runs great!