Keester,
A couple of items that I have read on these forums. I HAVE NOT tried them so it is hearsay.
The red tank for the TD is supposedly plumbed for FF so you may get an erratic run.
Someone said the BW runs best if you have the cylinder sideways and the vents on top running inboard and outboard.
One I have tried: If you want to try another tank/mount for the TD you might try the Norvel tank. It is clear and you can plumb the pickup however you want it. The TD mounting holes fit.
A Norvel engine might not fit the Cox red tank, however, the Norvel crankcase is just a little bit wider.

George