Dawn Redwood - safe to chop?

[cbrshadow23]

I'm located in the SF Bay Area (east bay) and want to pick up a mature Dawn Redwood. A neighbor is willing to sell me his potted dawn redwood which is pretty big. Could it withstand a trunk chop to be more bonsai-like? I'd also prefer to chop it before bringing it home to make transporting it much simpler.
I'm used to tropical bonsai/yamadori where it's no issue to do a trunk chop for the health of the tree, but I'm not as familiar with Dawn Redwood requirements.
Here's a picture of the actual tree.

 

[cchpg29]

My redwoods are pretty hardy. I would air layer. Looks like you could get several.

 

[cbrshadow23]

Is now a good time of year to give it a chop? Where on the tree would you suggest I chop it? Is it important to have foliage below the chop point?

 

[cbrshadow23]

bump

 

[crookedwoodbonsai]

IMO. would you you a big branch near to the base of each new air layer to

 

[TN_Jim]

how much?

 

[Shibui]

I have a few Dawn redwoods and they cope with chops very well. I'd leave at least one branch to be safe. Pretty confident they will bud on bare wood but cannot remember if I've actually done that - you will find out when you chop this one if you chop low.
Dawn redwood also grow easily from cuttings.
At this stage it is probably not really important where you chop because in the next growing phase things will change considerably and it is almost impossible to predict what it will look like then.
For taper and to allow a new apex to grow you really need to chop way lower than any proposed bonsai height you have in mind.